I'll try to answer your questions to the best of my ability, but keep in mind it is only my personal opinion:
1)Pricewise-What is cheaper to get?
Depends, Beetle prices tend to skyrocket and Type 3s are not as popular yet in SA as in the rest of the world. Chances are that you might get a Type 3 for less than a Beetle, especially in your part of the country. (I saw a few Type 3s about 5 years ago on a farm near Luckhoff, not too far from Orania)
2)Parts wise, which car is easier to get parts for?
Depends once again on what you are looking for. Body parts, windows and brake system parts on a Type 3 is quite hard to find, but it basically shares the same engine parts as a Beetle. Normal maintenance parts (fan belt, plugs, coil, points etc.) can be bought at any automotive shop. But then again the demand for Type 3 parts are also a lot less, you might get lucky?
3)Which car has better handling? I spoke to a guy who reckons that the Type 3 handles much nicer than a Beetle, is this true? Because they both share the lethal swingaxle

Type 3, for certain! More aerodynamic, and with a (claimed) lower centre of gravity, sticks to the road better. Automatic Type 3s have IRS and disk brakes.
4)Which one can be made to go a little faster with minimal effort?
Most probably the Beetle, cause you don't have the limitation of the decklid over the (flat) engine, and bolt-on performance parts are all designed for Beetles. But on the other hand, a standard 1700 Type 4 engine from a 411 or 412, or a 2liter Kombi engine is a straight fit to a Type 3 with no modification. (Ask Eben and IMPI

)
5)Disk brakes-Can the same kit be fitted to both cars?
I can't see why not
Thanks!!I apologise if the questions may seem stupid

, but there seems to be a lot of knowledge on this site
There is no such thing as a 'stupid question'. People who don't ask questions are stupid!