Hi:
One of the former members (former member AFAIK) used to rewind some of the 500 series transformers.
He is now? on Tekscopes2.
Don't know if he is doing it anymore.
There is also a litany of discussions, plans, YouTube videos, of failures (and semi-successes) about winding, coil winding machines, and 'potting'
AFAIC there ought to be a reasonable way to deal with replacing these transformers, and generating the high voltage needed.
But 'ought to be' doesn't mean there is
--
Roy Thistle