Back on topic, Sorry!

couldn't you mill a knob out of aluminuim (aluminum) or anything else just on a lathe? It doesn't have to match the original perfectly except for outer diameter, overall length and inner spindle diameter and even the it just has to be big enough to get a rubber grommit in to hold the shaft.

interested anyone?

If it were aluminium, you could have it anodised. Imagine, a black knob. I'll leave it there.

Murray 06000047
I don't think, therefore I am not.