WTB-Colt half circle bolt carrier

Looking for a half circle Colt bolt carrier with an unshrouded firing pin.

Can trade for a full circle, shrouded RRA ‘Enhanced carrier’, or stainless JP ‘full mass tactical carrier’ or puchase outright.

I’ve got one in a Franken-rifle I could trade you. What’s different in a Rock River enhanced bolt carrier?

RRA enhanced has a fully shrouded firing pin (like an M16) and a heavier than normal rear area of the carrier (but not as full as a M16 carrier).

If found one from a member here.