materials question

[hydrolagus.livejournal.com]

I found a pair of boots at a yard sale that actually fit around my calves. Problem is, the heels are worn down past the cap, so past where a repair place will usually fix them. Is there something I could use to build an all new heel or fill in the missing area? It would need to be able to stand up to my walking and dancing on it without shattering or overcompressing. In the absolutely stunning version of reality, I would rebuild them with soles like these, but I'd be happy with just normal wearable boots.