I don't know how to find all the flights into BOS and their prices but you can do the reverse on flights.google.com. Put in BOS as the origin, leave destination blank, and filter to non-stops only. That will show you prices from BOS to various airports, and while there's no guarantee, 1-ways in the other direction may be the same price.

Hoping someone else comes along with exactly what you're looking for because I'd like to know too.

Or you could just pick an airport with a decent amount of competition that's convenient to your drive and punch it into Kayak. For example, I bet you could find cheap 1-ways from BWI or DCA.