R stamped M1911 barrel

I have a barrel from an M1911, SN 298xxx with a barrel stamped "R P" vertically. I know the "correct" stamp is "H P" for this period. I haven't been able to find a definitive answer to who this inspector was or where the barrel originated from. Can anyone shed some light on this?

Maybe Rice, but that's just speculation. I don't have any information to back that up.

Julius Kosan had a 1911 with a R on top of barrel serl #302xxx I have all his old serial number list and Chuck Clawson too& many other things from the making of his books .