DOn't get a bluebird donor car! FWD sr's are a different best and can't be turned round to rwd. Get a silvia motor.

You could buy up every sr conversion part from maddat and you still wouldn't be at 22k and the maddat stuff is designed around the fact that the average backyard hobbyist should be able to do 90% of the work themselves. If you've got the patience go that route you'll learn a lot more about your car that way and the maddat gear is good quality stuff which will make the conversion a hell of a lot simplier even for some one with no experience.
I'd ring and talk to maddat and get them to explain the process for you. I think you be surprised. Even if you farmed some of the other stuff out like welding in the maddat tunnel, mounting intercooler and runing piping and exhaust etc you should still be under 22k.

Or just do what I did, buy a welder/a datsun and a sr and just learn as you go :) just factor in it taking a couple of years!