Look in the pawnshops, I found one made in 1987 by a Tiawanese company which is 900W,for R250-00.
I also have a big old one(1,5kw,1972) that I bought in the Junkmail for a grand.
Impossible for me or my guys to break.
Check the body,if it has a boep and you can`t put a flat bar from one disc to the other, the motor is worth it,
will definitely be big enough.All Wallmart(Makro,Game,Builders,etc.) grinders are underrated for all work, but chisel sharpening.