ok just got back, sorry I didnt get to your PM in time.
1: you will have to use the 4age pulley either way, also the toothed cam belt drive pulleys as well.
2: 11.3:1 with a stock gasket and probably over 12:1 easy with the 0.5mm gasket, assuming your pistons don't hit the head.
3: no one can determine this over internet pics, see an engine builder. Also the size of the pistons need to match the bore exactly, keep in ind there are 3 different "81mm: toyota sizes alone