The slide on the SR40c is thicker in several areas. The conversion would be possible if you started with a SR40c and then bought a conversion barrel. Like going from a Glock 23 .40 to a 9mm. The 9mm conversion barrel would be machined to fit in a larger muzzle end OD and also in the chamber/hood. You can only go in one direction with a conversion set-up. Another potential hurtle would be the extractor profile and if a Sr40c slide would cycle 9mm without modifications to the extractor.
I would buy a 9mm barrel for my SR40c....if it works. I'll take one extended and threaded too :wink: So now all we can do is hope for someone to bring it to market.