https://palmettostatearmory.com/psa...trigger-black-no-magazine-516444743.html

Or this for $80 less.. I have both of them. Super easy to order. There is a drop-down menu and just pick your gun shop.

https://palmettostatearmory.com/psa...rigger-black-no-magazine-5165447963.html

This in MK 1.9 would work

https://www.whiteoakarmament.com/3-gun-uppers.html

You might get more responses in the AR forum

The never-ending flight
Of future days.
Paradise Lost. Book ii. Line 221