I have checked the 2011 38th Edition Krause 1901-2000 and Hern's Handbook on South African Coins & Patterns 2012 and they both agree (for once!) that this coin listing should have another line added for the Proof mintage:
ND(1952) 1,698,000
ND(1952) Prooflike 12,000
ND(1952) Proof 16,000
Please could one of the team members do the honours. Many thanks, Rick