43 Air School in Port Alfred, South Africa have been doing JAA training for a while now. They might be able to guide you on this. You will have to sit the JAA exams (I assume you'll sit the ATPL exams as there is no point in siting the CPL exams) in the UK. It might be possible for you to do the flight test in SA as I believe 43 sometimes have a UK DE come out to SA to do this for there students but check with them.
You'll also need a Class One medical and since this is an initial examination I'm pretty sure you'll have to do this at Gatwick first, thereafter Philip Buys in Pretoria can renew your JAA medical each year at the same time as your SA medical though there are two separate fees for doing this.
The whole process is neither cheap nor easy. The studying is more than what you covered for the SA licence.
Need more help/info? PM me.
