re: OT mechanics, question

Ouch. If it just started knocking, you may be able to salvage the cam and the rods. If so, it's just the rod bearings and they can be changed out pretty easily. But you will have to mic the cam and rods to tell. I wouldn't recommend that if you've never done an engine rebuild.

You can find good low mileage motors at the junkyard. You should be able to find something in the $1500 range pretty easily...possibly much less. New or rebuilt they can be had for around $2000 if you do your homework and aren't afraid of a road trip. But realistically you should be able to have that one rebuilt for much cheaper than the cost of a motor and having someone put it in.