someone I know has a 3sgte and he said that it is really hard finding parts for his motor? anyways... there are a few motor + trans combos... but those only come in AWD. If you are trying to get RWD I would also suggest a 2jz like supras/sc300/and is300. there are a lot of trannies for 2jz and parts are REALLY easy to find.

The only problem I think you'll have is fitting the engine in there because it's about the size of a v8? Personally... I would suggest buying a is300/gs300/or sc300, it's a toyota and they are all rwd.