IslaWW Yes, thanks, pour-able two part foam is one of the items I have in mind but prefer to have it removable so the sock and/or shoe can be replaced. It will fill the sock toe then fit part way around a standard cane tip. This is the reason I want to make a form to make the shape, poured or carved. Urethane density can be changed to get the best possible firmness.
Euan, thanks for the info, I'll check it out.
You will get old if you live long enough!