This is another elk leg bone. I think its the front leg shin bone but I could be wrong.
The ring nuts I make, there not all that difficult to make if you have a drill press but they could also be made with a hand held drill. Most of my older knives the nuts were made from 3/8" rebar. I'll drill two holes in them, one for the ring and one down the center that is then taped with a 10/24 since that is the size I find works best on my knives. I make two different types depending on the application. The one that I make when I go for just bone is made with a tapper so it feels the hole in the bone and also penitrates it as it is tightened up. The ring has a two fold mission as a lanyard hole and also something to hold onto when you tighten it up. The other type of ring nut is for when I use a butt plate so it doesn't have to be as long. To shape the ring nut I'll grind to remove most of the material and then I'll turn it with the drill and finish it off. No two are ever the same. For my ring I am now using 1/8" W-1. Pretty simple, either drill a whole in a 1/2" round or make a slot. Stick your ring material in either and heat up your ring material up and walk it around the round. After you have the coil make up cut it with a small abrasive wheel and now you got rings. You'll have to make the hole in the nut for the ring oversized if you want it to pivot. I'll then weld it shut. I find all it takes to do this is to butt the two end and take the smallest tip I have and heat it up till it sparks and it normally welds it self together.
Hope I didn't lose you.......Ray