If you dont know how to drive a stick you dont want a z28 6 speed. The rear ends in these cars are weak and if you dump the clutch too many times it'll snap. The v8 is crammed in there and very tight and expensive to work on. The distributors are a weak point of the car, under the water pump (when it goes out it all goes out)........water pump is around $200 and distributor is around $400(only use a GM one) I could go on and on......If its just to get ya around get a auto. Z28 or the v6. And there should be plenty in that price range, look on craigslist and autotrader.
Look here, scroll down to the 00 Z28.....auto, convert., and only $7k for one with a LS1. Little more than your range but well worth it.
http://cherokeeauto.com/