gm crate motors arent expensive and are very reliable.i personally wouldn't buy one off ebay.
got mine from advance auto parts and it had 3 loose main bearing bolts and a bent pushrod!it was only a grand but i couldn't find much info about it before i bought it,and wound up with smogger dished pistons and 58cc 305 heads.a diffucult way to build a performance motor!
i think the gm units start at around 2100 bucks.
you get what you pay for
86 camaro,383,topline vortecs,scat crank,wiseco forged 9.5:1,6"scat rods,comp xs282s,performer rpm,750 proform vac sec,msd in cap, hooker coated 1 5/8"headers,3"flowmaster,700r4,2800 stall,3.42 10 bolt posi,hotchkiss lca's,aje tube k member & a-arms