Mark,
I had to make them for my 10500 series fire truck. They are 1-1/2" thick, so I went to my local industrial rubber supplier and got a piece of scrap that they use for snow plow cutting edges. I used a hole saw in my drill press to make them round. The edges aren't smooth like original, but they work! My truck required 4 pieces, one on top and one under the bracket on each side.
Mike B
