Should I build this Chev engine?

A friend has a throttle body 5.7 Chev engine that he would sell for $100. It's about a 1994 or so. He got it from a wrecking yard, installed it and found it had no oil pressure to the top end. Had pressure at the gage though. Has Vortec heads, some brackets, the throttle body manifolds. I have a tired 1980 350 in my Scout and was thinking this would make a nice replacement. Help me make up my mind.