I understand that casting the Avengers in 1970 is very odd, however, I’m getting quite tired of seeing the same teams and the same casting picks. Sometimes the actors are undeniably perfect for several roles and sometimes a team is just waiting out there to be cast by true fans. But here's something else to check out in between the others. The Avengers were brought to us in 1963. If CBM’s were as popular then as they are now then the Avengers, with out question, would be presented to us on the silver screen. 1970 was the Golden Age of action stars and I will present to you the toughest cast ever. Keep in mind that, although these actors may appear older as did everyone from this era (check out some old family photos for proof), they were the appropriate ages in ’70 for a group of hardened heroes. Here, due to budget, FX, and a need to present the most popular group, this team is led by Cap and consists of the original line up (sans Hulk) and would be up against the original Masters of Evil, led by Zemo and gathered by Enchantress. She would not involve herself in the battle as women, in ’70, were not thought of as equals (I disagree), but she would be the mastermind behind it all. The final battle would pit: Cap against Zemo, Thor and Executioner, Iron Man and Radioactive Man, Giant-Man and Wasp against Melter, leaving Black night to square off against the assisting Namor. As an old friend of Cap and someone who Marvel would want to bring to the mainstream if this were the year of the CBM, he would be a great replacement for the Hulk (cheaper and easier to cast, as well). All of the bio info is taken from Wikipedia. Thanks wiki

AVENGERS
Steve McQueen as Captain America
Captain America was reintroduced during the Silver Age of comics when he was revived from suspended animation by the superhero team the Avengers in The Avengers #4 (March 1964). Since then, Captain America has often led the team, as well as starring in his own series.
McQueen was nicknamed "The King of Cool. His persona made him one of the top box-office draws of the 1960s and 1970s. McQueen received an Academy Award nomination for his role in The Sand Pebbles. His other popular films include The Magnificent Seven, The Great Escape, The Thomas Crown Affair, Bullitt, The Getaway, Papillon, and The Towering Inferno. In 1974, he became the highest-paid movie star in the world.
Charlton Heston as Thor
Debuting in the Silver Age of Comic Books, the character is based on the Thor of Norse mythology. Thor has starred in several ongoing series; limited series and has been a perennial member of the superhero team the Avengers, appearing in each of the four volumes
Heston is known for having played heroic roles, such as Moses in The Ten Commandments, Colonel George Taylor in Planet of the Apes, El Cid, and Judah Ben-Hur, for which he won the Academy Award for Best Actor
Matin Sheen as Iron Man
Tony, he is an industrialist playboy and ingenious engineer who suffers a severe heart injury during a kidnapping in which his captors attempt to force him to build a weapon of mass destruction. He instead creates a powered suit of armor to save his life and escape captivity. Throughout most of the character's publication history, Iron Man has been a member of the superhero team the Avengers and has been featured in several incarnations of his own various comic book series.
Roy Sheider as Giant-Man
Pym debuted in a seven-page solo cover story titled "The Man in the Ant Hill" (about a character who tests shrinking technology on himself) in the science fiction/fantasy anthology Tales to Astonish #27 (Jan. 1962). Pym was revived eight issues later as "Ant-Man", a costumed superhero who starred in the 13-page, three-chapter story "Return of the Ant-Man/An Army of Ants/The Ant-Man’s Revenge" in Tales to Astonish #35 (Sept. 1962). In September 1963, Lee and Kirby created the superhero title Avengers, and Ant-Man was established in issue #1 as a founding member of the team.
Scheider was an American actor. He was best known for his role as police chief Martin Brody in Jaws, as choreographer and film director Joe Gideon in All That Jazz, detective Buddy Russo in The French Connection and his role as Captain Nathan Bridger in science fiction television series SeaQuest DSV.
Natalie Wood as Wasp
During her run in Astonish, van Dyne also joined Avengers in its first issue, along with her partner, Hank Pym. It is on this team that Janet became most well known, at first the weak link of the team, but later on one of the smartest and craftiest members.
Wood began acting in movies at the age of four[2] and became a successful child actor in such films as Miracle on 34th Street (1947). A well received performance opposite James Dean in Rebel Without a Cause (1955) earned her a nomination for the Academy Award for Best Supporting Actress and helped her to make the transition from a child performer. She then starred in the musicals West Side Story (1961) and Gypsy (1962). She also received Academy Award nominations for her performances in Splendor in the Grass (1961) and Love with the Proper Stranger (1963). Her career continued successfully with films such as Bob & Carol & Ted & Alice (1969).
John Saxon as Namor
(Retconed) When World War II broke out, Namor put aside his differences with the surface world, and he fought alongside the team of Allied heroes that called themselves the Invaders, namely Captain America, his sidekick Bucky, and the original Human Torch
Saxon appeared primarily in supporting roles, and won a Golden Globe Best Supporting Actor nomination for his portrayal of a Mexican bandit in the 1966 film The Appaloosa. He again played a Mexican, this time a revolutionary named Luis Chama, in 1972, supporting Clint Eastwood and Robert Duvall in Joe Kidd. In 1973, he appeared in Bruce Lee's Hollywood debut Enter the Dragon, which was Saxon's most famous film.
The Sorceress
Faye Dunaway as Enchantress
Amora became one of the more powerful magic-wielders in Asgard, with her magical arsenal focused on (but not limited to) charming and mind-controlling people. Her by-now well-renowned beauty did not hinder in this. In her first appearance, she attempted to eliminate Thor's love interest in order to have the thunder god for herself. From her first appearance, she was assisted by a powerful minion — Skurge, the Executioner. The Executioner loved the Enchantress, but she merely kept stringing him along with her feminine wiles, using him as her muscle.
In 1967 she gained the leading female role in Bonnie and Clyde opposite Warren Beatty, which earned her an Oscar nomination. She also starred in 1968 with Steve McQueen in the caper film The Thomas Crown Affair. She worked with such leading men as Dustin Hoffman, Charlton Heston, Paul Newman, Robert Redford, Tommy Lee Jones, Jack Nicholson, and Robert Duvall.
Masters of Evil
Charles Bronson as Baron Zemo (there’s no way I’ll let any of you tell me this 1 doesn’t work. You can’t have an action monie in 1970 w/o him. He can’t take the mask off, even though they probably would just to show that it’s Bronson. Also he’s 49, and 25 years after the war ends, 49 seems reasonable)
Zemo was one of the top scientists in the Nazi Party. A brilliant, if sadistic, scientific genius, Zemo created many weapons of mass destruction for Hitler's army. Heinrich Zemo's intelligence was only matched by his sadism, as he routinely tested his deadly weapons on innocent people, both prisoner and civilian inside the Third Reich. His activities ultimately drew the attention of Captain America, resulting in a confrontation just as Heinrich was ready to unveil his newest scientific breakthrough: Adhesive X, an extremely strong adhesive that could not be dissolved or removed by any known process at the time. Captain America threw his shield to release the adhesive from its vat, onto the ground. Unfortunately, Zemo was standing right next to the vat containing the chemical, pouring it over his hooded face. The adhesive quickly seeped inside and permanently attached the hood to Heinrich's flesh, preventing Zemo from ever removing his hood. Zemo tied the Cap and Bucky to the experimental plane, which was now booby-trapped to explode, and launched to their deaths. Captain America fell from the plane as it exploded, and Bucky was apparently killed. Zemo fled to South America as Hitler and the Nazis fell and World War II ended. As decades passed, Captain America was ultimately revived by the Avengers, causing Zemo to renew his rivalry with the Captain. Heinrich formed the Masters of Evil to serve as a villainous counterpart to the Avengers.
Charles Bronson was an American actor best known for his "tough guy" image, who starred in such classic films as Once Upon a Time in the West, The Magnificent Seven, The Dirty Dozen, The Great Escape, Mr. Majestyk, The Mechanic, and the popular Death Wish series. He was most often cast in the role of a police officer or gunfighter, often in revenge plot lines.
Christopher Lee (yup that one) as Executioner
Skurge has always had feelings for Amora, the Enchantress, and regularly aided her in various evil schemes to gain control of Asgard. However, the Enchantress only manipulates him, using her charms to keep Skurge under her thrall. Loki, the trickster God, also has used Skurge many times.
Christopher Lee initially portrayed villains and became famous for his role as Count Dracula in a string of Hammer Horror films. Other notable roles include Lord Summerisle in The Wicker Man (1973), Francisco Scaramanga in The Man with the Golden Gun (1974), Count Dooku in the Star Wars series, and Saruman in The Lord of the Rings film trilogy.
Bruce Lee as Radioactive Man
A nuclear physicist and Communist agent in the People's Republic of China, Chen Lu first appears in Journey into Mystery. Ordered to find a way to defeat the Thunder God Thor - who thwarts the Red Army's invasion of India - the character exposes himself to small doses of radiation until he is able to endure a massive barrage, becoming a living "Radioactive Man."
Lee was invited to an audition, where Lee so impressed the producers with his lightning-fast moves that he earned the role of Kato alongside Van Williams in the TV series The Green Hornet. The show lasted just one season, from 1966 to 1967. Lee also played Kato in three crossover episodes of Batman. This was followed by guest appearances in a host of television series, including Ironside (1967) and Here Come the Brides (1969). In 1969, Lee made a brief appearance in his first American film Marlowe where he played a henchman hired to intimidate private detective Philip Marlowe (played by James Garner). In 1971, Lee appeared in four episodes of the television series Longstreet
Sean Connery as Black Knight
Professor Nathan Garrett, a biologist, is the direct descendant of Sir Percy, and found Sir Percy's tomb and the ebony blade. Garrett's evil tendencies make him unworthy of wielding the sword, and he is shunned by Sir Percy's ghost. An embittered Garrett then devises an arsenal of medieval weapons that employ modern technology and genetically engineers and creates a winged horse. Calling himself the Black Knight, Garrett embarks on a life of crime to spite his ancestor. After a battle with the hero Giant-Man Garrett joins the supervillain team the Masters of Evil at the request of master villain Baron Zemo
He is best known for portraying the character James Bond, starring in seven Bond films between 1962 and 1983 (six "official" EON productions films and the non-official Kevin McClory-helmed Thunderball remake, Never Say Never Again.)
Donald Sutherland as Melter
The character debuted in Tales of Suspense #47 (Nov. 1963) as an industrialist who specializes in providing munitions to the United States government. After an initial encounter with hero Iron Man, the character reappears in Avengers #6 (Jul. 1964) as part of supervillain team the Masters of Evil.
Sutherland began to get small parts in British films and TV, landing notable roles in horror films with Christopher Lee. and twice appearing in The Saint, firstly in the 1965 episode "The Happy Suicide" and then, more auspiciously, in a story called "Escape Route" at the end of 1966. The Dirty Dozen in 1967, with Lee Marvin and Charles Bronson; in 1970, as the lead "Hawkeye" Pierce in Robert Altman's MASH; and in 1970, as tank commander Sgt. Oddball in Kelly's Heroes, with Clint Eastwood and Telly Savalas. During his time in England Sutherland also appeared in The Avengers in 1967, in an episode titled "The Superlative Seven."
This movie, if given the respect, could have started the boom of CBM’s.