Time for new engine in 72 Swinger - What Would You Do?

Yep, find a good cheap verified good engine, pop it in there to make it a running driving car again, and include the grenaded engine with the sale, because the next guy/gal may want to fix it and put it back in. Definitely not worth a Hemi swap or anything crazy like that. Don't get more behind the 8-ball than you already are.