That sounds like a pretty good deal for that Quad-4 cradle/transaxle. (I'm considering between that and a 3.4 TDC.) As for the Quad-4 itself, you might want to watch out for what engine you're buying. Sounds like a regular Quad-4, with about 140 HP (I believe) stock. Rebuilding it to Quad-4 HO specs (180-200 HP) would cost you a couple thousand dollars going by the last place I priced it at (and I can't find the printout I made of their parts list anymore).
In any case, good luck in whatever you end up putting in there.