Uzi for the JP36. It should be pretty easy to do, too, just use the models and animations from the Uzi already in the game. No need to experience the headache that I imagine comes with trying to play around with imported models.

The attachments would be pretty easy, too. Stock parts would a be a 1-1 replacement, Polizei Special foregrip would be the Uzi's Tactical Foregrip with the regular vertical foregrip, compact foregrip would be the Uzi's Tactical Foregrip with the stubby vertical grip from the CMP/SpecOps and maybe also a shortened barrel (if you can modify the model, and the position of barrel extensions when that attachment is attached), Sniper Stock would be the Uzi's Ergonomic Stock, Solid Stock would either be the Uzi's Folded Stock or the stock removed entirely.

This mod, in addition to having some nice novelty because it would be an SMG for the primary slot, would actually make a lot of sense since those two weapons have nearly the same base damage and rate of fire in-game. In the conversion to a primary weapon, the Uzi trades some concealment, accuracy and a tiny bit of damage for bucket-loads of ammo, better ammo pickup rate and a tiny bit of RoF.

This would actually be great, please do this! :)