Post to South Africa?

Hi everyone, I have a few cards on eBay and I have had a request from someone wanting to see if I would post any cards registered post to South Africa. Has anyone had any problems sending to South Africa and if my listing says no international postage can that be changed to allow international post after people have placed bids?
What do you think?

We post a reasonable amount of stuff to South Africa through work and even though its registered and express it seems to take a long time to get to it's destination (anywhere from 1 - 6 weeks) but we havent had anything go missing.