Sorry to hear about your heath issues, and giving up your car.
That said, for a 1970 Cuda, 383 auto, in the condition you say, it would be a good deal for someone (and move quickly) in the 5-6 thousand dollar range. If you have parts to include, new front end, sheet metal and the like, and it is a desirable color, or cool options, you could ask a little more. If you don’t mind waiting for it to sale, I would ask up to $8000 - $9000.
Rust issues will scare away a lot of buyers.