This is a neat project - sold new out of Lake Mills, WI according to the Marti report. Looks like it had some T/A style modifications that took place years ago. Would be a cool project to restore in some type of vintage racing trim.
For $17,500 I think you could do worse. I'd be in around $12k if I were in the market for a Boss.
Link to 1970 Boss 302 Project auction
9F02G193972