I used Conroe Taxidermy to mount a kudu and a red hartebeest from my plains game hunt in Namibia. They are very experienced in working with African game. I'm very happy with the job that they did. They are a little on the expensive side, but taxidermy is one area where you really get what you pay for.

http://www.conroetaxidermy.com/

Africa Hunting Safaris, Cape Buffalo Hunting, & Other Big Game Hunting Adventures