if your going the custom route i would say find a nice 4wd and convert it. here are three in the sf bay area in your price range. i bet you can make some your money back selling the 4wd stuff on this forum. i got mine off craigslist. i scored a choice 72 CST 4wd for 2500. the po was kind of a stoner, didnt know much about blazers. he only had the truck for a month says he bought it just to go to "burning man" i didnt think it was my job to let him know he could have got twice as much as i gave him. he didnt know that the top came off and "wondered why the guy he got it from would put aluminum heads on it since cast iron is much stronger than that aluminum stuff" go figure
http://www.craigslist.org/eby/car/118741863.html
http://www.craigslist.org/nby/car/117934301.html
http://www.craigslist.org/eby/car/117816117.html