I generally buy AppleCare online using my credit card.
The actual product is only a "serial number", so you can also ask oversea's colleagues /family / friends etc to do it also if you don't have a card. If you know someone with a student card, its cheaper too.
Retina 15" Applecare is about R3150 though with currency conversion (RMB1650 at moment where I am in Shanghai, China this week), so its not a cheap purchase!
Peace of mind though is worth the extra money, especially when its a R28,000 laptop..
As for locks:
http://www.cultofmac.com/251172/the...ves-the-retina-macbook-pros-security-problem/
http://www.tuaw.com/2014/01/29/pny-thinksafe-macbook-locking-system-perfect-for-those-macbooks/