I'm new at leatherworking and am assembling a special purpose type of dog collar. These are special purpose, not to be used for attaching a leash, so just trust me on this (I just don't want to explain as it's involved). These need a keeper loop on them, and I think the best construction is to use a rivet. In shopping for the rivets and tools, I'm having trouble figuring out the tool sizing.

The way I want to do this is:

(with all the correct holes punched) slip the post end of the rivet through topside of the collar, under the loop. This will put the rivet bottom on the outside of the collar, but semi-hidden under the keeper loop. The set the top of the rivet on the backside of the collar. I plan to use double-headed rivets so it should look fine. I'm also thinking that I could slip the anvil through the keeper loop to hold the bottom while I set the rivet top, but I'm not sure if they sell anvils that are roughly 1/2" wide.

Is this doable? What size rivet setter should I look for?