On Mon, 06 Jul 2015 15:40:51 -0700, Uncle Monster wrote:

Perhaps you could take some rubber from a bicycle tire and cut it to
size?

This is a great idea, and is the type of idea I was hoping to get.

The bicycle tire is just a tad too small to fit around the heel of this
boot, as it's a cowboy type, but the idea is sound.

I was thinking about the rubber of a car inner tube, which is a bit too
soft, but certainly it will do in a pinch for the rubber layer on the
bottom.

I went through my leather pile, after autopsying an old catcher's mitt
and assorted and sundry shoes, and there was an old boot (another pair)
that I may cannibalize the upper leather of, but again, it's thinner than
the heel leather.