needed: M-16 pistol grip

I figured it out! The threads in the grip of my M-16 are stripped and the motor plate drops out of place and so the motor dis-engages with the bit its supposed to work with. And here's me ripping the thing apart, rebuilding and testing. Of course after ~3 test shots the plate works loose again and make the buzzing bees noise.

So...does anyone have an M-16 pistol grip for lease/rent/sale?
B.

I'd like to say I did, but sorry no. Of all the spare parts, that's not one of them.