The South African currency is the Rand, of course, so I don't know about this Pound business. Unless he thought English audiences were unaware of South African currency nomenclature, which is entirely possible. Anyway, the average weight of a Rhino is about 4500 pounds, so if we assume Fitty is 175 pounds, then it would take approximately 25 units of Fitty to equal a rhino. So a better name would 1,250 Rand.
I hate to spoil a nice idea with math, but it's important to be scientific when you're naming rhinos after rappers.
