I wondered about something like that plus a hairdryer to make it neat.
I've been looking at 1000d fabric, but come up against the issue of how to fix it to the boot, as it sounds like it can't easily be glued (and I'm not going to spend >£100 to try out Bondit B-4x).
I don't think you even need fabric. Just squird some shoo goo on and move it with plastic spoon. It'll then be the protective surface. It's tough stuff.
I've used shoe goo to repair a lot, works well.
For the heal but I'd be tempted to just put some gorilla tape on though.