At your age, get yourself a working holiday visa, spend a year in the UK sweating your bollocks off doing whatever pays best saving every penny then get back and polish off the rest of your CPL.
NB On a SA PPL you can fly in the UK, on aircraft types you're rated on in SA, usually subject to a check ride, but I'd guess you'd be looking at +/- £100 for an hour in C172 so perhaps not the best use of finite funds, but good to know if you need a flying fix.
Rgds
GT