What trans should I run?

get the stick! i think 700 bucks is a little steep, maybe try 600 or 650? either way, you will need to factor in all the little things like bushings, clips, seals, etc....its the little stuff that adds up quick. and if i was you, if this guy is really confident in what he has, ask him to pop off the cover for you. It doesnt take long to do on an 833 and hell then you'll really know what kinda condition its in internally and if it will need any other parts

oh, and from what i have heard many others say, that 833 will be fine...your not even testing it with that kinda power

good luck!