Don't go cheap! I got one from someone selling on a forum (and you know who you are) with disastrous results. The first one had intermix--I mean pushing the oil out the rear main intermix. The second one he sent as a replacement had the cams mis-timed. Corrected that, and it seized after 5 minutes. So I'm at $6000 in without a running car. Just go to a reputable seller with a warranty.
Oh--and I'm getting really fast at engine replacements.