swamper8

Greetings all,
My cousin has been offered a 1997-2003 style Malibu. It was diagnosed by a mechanic as having either a bad lifter or bent push rod. It makes a pretty hefty clicking/knocking noise while running. I am a well seasoned driveway mechanic and have no problem pulling the intake, heads etc to fix the problem. My question is does anyone think it's worth a repair vs. putting a low(er) mileage motor in from the junkyard? I wonder if just putting in a new lifter (or lifters) would be sufficient to quiet the problem or can I assume that if a lifter is tapping most likely the lifter bore is also going to be out of spec? (out-of-round or just too large in diameter etc) The cheapest thing to get it on the road would be just to replace the lifter but if there's a good chance the bore is probably shot I will probably just recommend we put in a different engine.
Thanks