So far in my research into Holsters for the SAR K2P 9mm, the following fit:
Fobus Paddle Holster #SP11 (No retention, but fits like it was made for it)
Crosman Generic Pistol Holster P/N SAH02A510 ( often found at Wally World and other stores, usually around $10 )
Tagua Open Top Leather raised OWB Holster #BH3-635 (Black, Right Hand) (Will require a bit of Stretching for use, but fits tightly) (Made for Springfield XD-S)
I have a few other Holsters, such as a fairly generic vertical shoulder rig that also fits, but it is no longer made.
I'm sure there are other good Holsters for this fine Pistol, so feel free to add them here.