Mike: I'd buy the cheapest pair I could find new, and take the time and grind/trim one side of them down almost flush to the insert. I would leave a small amount of metal, like .030" or less, to be able to fully support the inserts. If one has the gorilla grip and breaks them while removing a ring, maybe they need to try the ring by hand, without tools. 

I'm not above modifying a tool, new or used for a very specialized task. Had lots of them when I worked on the production floor.

Craig

KF5JOT