Paul Cook and I spoke about this a while ago. In preparation for the day when I'm fabulously wealthy, I bought a beater Remington 788 in .223. That's the start. Big advantage here is rear locking lugs, so the stubby pistol cartridge doesn't have to o'erleap a canyon to get to the chamber.
We reckon Paul could machine out the top half of the mag well of a 1911 and make it play nice with the receiver. The boltface is close enough. Extractor and ejector should work. Bore the tube out to .356 (or whatever 9 para takes), shorten it up to a handy length, and there we are - a means by which I can use up the 9mm para ammo I have without having to feed it through a handgun, which I can't shoot for sh!t.
On hold as I'm retired and fairly brokeish. Will advise.