yeah i wouldnt immagine it could be that hard or expensive. you should be able to get a 2wd s-10 on eBay from the south (rust free) for pretty cheap. and 350s are EVERYWHERE so im sure you could get one of thse at a decent price too. if u want an automatic, i have a brand new 700R4 that i bought for my ol '88 350 full size, but i never used it. i can help u out with that if u want it. as a side note, if you could get a 2wd, regular cab fliarside (i think they only came in the GMC Sonoma) that would be PIMP!!!
o and as a sidenote, i always thought a LS1 swapped into an Xtreme Blazer would be the shit, but i dunno if thats ever been done, and i sure as hell dont wanna be the first to try hehe