I went to Home Depot and purchased x2 rubber sink drain plugs. They have a perfect ring that is already split ( No need to cut ). Literally under $2 each.
true dat. My first set I scratch built out of epoxy in a mold. But I over torqued my ring and it broke. Then I noticed one on a modular shotgun grip I had laying around the house and used that instead. But they can be had for just a few bucks. If you dont have a good gun store near you, try Brownells.com.
For the ring, I made mine. I first used what was basically a key ring, but it looked bad. So I bent my own out of some metal in my garage.