I incorporated the flying into a holiday, and wasn't exactly watching the pennies so my prices won't be much use to you. The Algoa website has some info on good local accomodation which won't break the bank.
If you need to validate a license over there I highly recommend you get a copy of
Irv Lee's Book which explains how to do it, and if you plan it in detail you can have your SA PPL within a couple of days. If you're learning, no such worries. Still a good read though, with many useful tips (like the fact that mag variation is 20 odd degrees!).
You can fly to either Joburg or Cape Town, then grab a connection to PE with Kulula (SA low cost airline). BA and SA airlines fly from Heathrow, or KLM from Amsterdam. Roll a dice as regards prices. Best option might be to get the cheapest flight dates you can, then arrange the everything else around them.