Well that would depend on how 'eye-bleeding' you wanted to go. Initially, I'd use anycast and locate the DNS endpoints in ZA and abroad at the major global IXP locations. For ZA most likely hosted at a selection of facilities such as INX-ZA/NAPAfrica (JNB/DBN/CTN) locations and internationally, well there are plenty of options but at least 4 other continents (perhaps South America,North America/Europe/Asia for distribution) So that's minimum 6 endpoints in ZA and perhaps matching number of offshore (additional east/west for larger markets if necessary). Each endpoint's configuration would vary but preferably HA with expansion options. That would be my garage registry 1.0 starting point.
Just to add: That's if I had to do it myself and not utilise PCH or some other service for secondaries etc.
Bit more than a garage all of a sudden.