I have always loved the early C3 Corvettes. They're actually a decent platform for building a pretty enjoyable car. The interiors are hard to stomach, ugh, but if you get them back to new-ish condition, they're okay. The black interiors have aged the best, imo.
One great thing is the high percentage of manual equipped cars.
That big block/4-spd car is not badly priced at all. Nice condition numbers-matching L36 4-spds are typically $40K or so cars.