The VC is shot
I don't know how to rewind it - the former deteriorated, too. My bigger worry is why it blew up - could there be an output transformer fault putting HV on it?
Anyway, I can hold out a while fora replacement speaker, putting a PM one in there just sounds like it'll be a headache, though I guess I can do it in a way that's reversible if I ever find the right speaker.