I wont to avoid patronising you - but are you aware that you will need to purchase a lot more than just the engine to "just drop it in" a little Datsun.

You could go down to any importers and probably have a non turbo motor for just a few hundred dollars, but as has been discussed many time here a number of other components that cost more than the motor need to be purchased.

Fuel pumps, gearboxes, tailshafts, diffs, brakes are just a few of the things that come to mind.

I only want to give you some indication of the pain and suffering you are "trying to get your hands on"....but with great suffering comes great rewards.

I'll stop know before I sound like some sort of Datto loving Jedi...