This may not be strictly in answer to your post since you asked about UK costs, but having just yesterday sent off all the relevant paperwork for my shiny new PPL, I can tell you that in Cape Town, South Africa, it will set you back in the region of R24000. At today's exchange rate of 1GBP=11.48ZAR, that's about 2090 pounds. Not including accommodation of course, but that can be quite reasonable if you are willing to look around. The weather also tends be a bit friendlier than in your part of the world, and the "occasional" (more like "perpetual") 15-20 knot wind makes you quite proficient at cross-wind landings.
However, remember that the longer it takes, the cheaper it feels.