go with the b16.you can do the whoe damn thing with the money you have.
its a good motor and they are not too pricey,trust me you will win a lot of races with just a stock b16.hell i got a stock b16a in a 91 si..u will beat any stock gsr if you can drive well, the mounts are like $500 buck from www.hasport.com they also sell the header you are looking for.www.ardperformance.com has the b16 you need in a complete swap i think shipping is like 4 or 5 hundred.not to bad shipped 2 your door or 2 a shop.good luck.