Mike,
You might contact the Powderkeg in the Johannesberg suburbs (google will get the details) and ask whether they would do the export paperwork and organize the shipping. (I'm assuming you are buying from a private seller.) If you are looking at Durban or the Cape to ship from, I'm less sure, although Bob Henry had a shop in Durban at one point. EDIT: It's the Natal Gun Company that is run by Alan Henry, likely Bob's son, but I do not know him. My Cape Town friends sold City Guns there, but the business is still open and may be a possibility.
Expect you know that if you've got an FFL, then you can do the U.S. side yourself, getting ATF to approve the Form 6. Otherwise, you'll have to find someone on the U.S. side, preferably in Alaska (!) to do the paperwork and bring the firearms in.
Regards, Tim
Last edited by Tim Carney; 11/08/12 12:22 PM.