My first vehicle! 1956 CJ5

[gmwillys]

Hockey pucks work pretty good unless you need taller mounts. Just drill a hole in the center, and there you go.

[bmorgil]

Like gm said, anything hard rubber will work. Depending on the thickness you need, cut pieces of conveyor belting also works extremely well. On my Jeep the mounts are the original thickness that came off, 1/2 inch thick.