I bought a pair of A-Wing fighters at a flea market, one of which was missing the cannons. I've modeled replacements for it using the parts from the intact one.
Note: The geometry for printing these is challenging, I've experimented with several different angles and supports and have had... intermittent luck. It's possible these are more of a 'me problem' than anything so best of luck!
Note: I made one small cosmetic change: The secondary cannon has a small indent in the front that was missing from the Kenner molds.
Plan to sand/cut sprue to clean up whatever supports you choose
There are no big flat areas that support a no-support build so some post-processing is probably necessary. There are crevasses if you print it vertically that may be very challenging.