I just picked up an 1865 Maynard sporting carbine. And it’s missing the nipple and what looks to be a small screw to secure the nipple. Looking online I can find replacement nipples but they are all threaded I do not see any threads where the nipple Goes. Did they make non threaded nipples that where help in place with a pin or screw. Any insight or a link to a replacement nipple that would work will be greatly appreciated.