Commodore Superpet video problem -- ideas?

Thanks for the suggestions. I've looked for visible arcs as carefully as I can, and have been unable to see any. I've cleaned and resoldered the connections to the transformer, and removed and cleaned the anode connection to the CRT. I don't know if you can remove the anode connection at the flyback end, so I haven't fiddled with that. Is it reasonable to assume at this point that the arc is *inside* the flyback cover? Is it possible that a component failure outside the transformer could cause arcing in the flyback, or does it mean that the flyback itself is at fault? The flyback transformer appears to be unobtainium (although if someone knows different, I'd love to hear about it). I guess I'm in the market for a PET video board.... Thanks again, Rob