Mike Colter, now I saw him in Law & Order. He played Joseph Koty. If you don't know who that is, look it up. lol. I don't know if he is actually African or not. But, if not he plays the accent very convincingly. I think he would be the perfect actor to portray Hunter. T'Challa's older brother known as White Wolf.
Sammi Rotibi, this man, had a very short role in CSI: NY. Once again, I don't know if his accent is real or not. But he was very convincing, and just from what I saw of him. His passion, and talent, I do believe he would be a great Black Panther.
Of course I didn't forget Djimon Hounsou. I think he should play King T'Chaka.