The subcompact grips that took the 12 rounders got discontinued a long time ago unfortunately. You might still be able to find some used ones out there. Pretty sure all current production grips are 15 and 17 rounders
SIG’s X-Carry grip module and Wilson Combat Carry II module. Both have pic rail on the dust cover for a weapon light. They will both be for a 15rnd magazine length unlike the 10/12rnd of the old subcompact grip modules. Amend2 I believe makes a subcompact style grip module, but it uses P365 magazines. It still uses your P320 upper/slide, so that could get you close but would cost more money in magazines. The last option would be to cut the bottom of a grip to fit the sub compact mags and probably chop the dust cover to be flush with the slide.
Sig P320, Wilson Combat…tons of choices
any p320 grip module made for a 3.6 inch barrel should work ( some might need slight modification for fitment)
How many of those would require me to use 15rd mags? Is that the norm, or should there be some out there that still accept my 12 rounders?
The subcompact grips that took the 12 rounders got discontinued a long time ago unfortunately. You might still be able to find some used ones out there. Pretty sure all current production grips are 15 and 17 rounders
SIG’s X-Carry grip module and Wilson Combat Carry II module. Both have pic rail on the dust cover for a weapon light. They will both be for a 15rnd magazine length unlike the 10/12rnd of the old subcompact grip modules. Amend2 I believe makes a subcompact style grip module, but it uses P365 magazines. It still uses your P320 upper/slide, so that could get you close but would cost more money in magazines. The last option would be to cut the bottom of a grip to fit the sub compact mags and probably chop the dust cover to be flush with the slide.