I got a bit ahead of myself!! The foot rest is made out of aluminum and the original was cast. I had a look around my "Don't throw that away pile" and low and behold I find a piece of aluminium that just happened to be the correct thickness and to my total astonishment it ALSO just happened to be the same diameter
. I don't know what the odds of that would be but it was the only piece of ally there. Anyway just good luck to me.
I used my horizontal mill to put the diamond lines in it for non slip as per the original.