[Steve D]

I opened up the coil covering as far as I could in the frame and the open is definitely not at the terminations. So it appears that I have three options: 

1. Buy a modern perm. magnet replacement and add a chassis choke and resistor - not very original and a last resort.
2. Find an OEM replacement on Ebay - A preliminary search was not successful.
3. Try to press out the pole piece and rewind the coil - I'll try this first because what have I got to lose?  If it it doesn't work I'll go with one of the other two options.

I have a 20 ton press in my garage and can use some pipe as an arbor. I think you guys are right that it should be pressed out from the rear and it might have a centering step. I'll know more when I get the cone out. The voice coil and spider assembly are held in with two screws so all I have to do it loosen the cone edge from the frame with some acetone and I think I can get the cone and voice coil out without damage. I am a engineer with a high voltage power supply company and have facilities to rewind the coil at work so that should not be a problem.

I want a permanent fix and I don't think that fusing the open wire by zapping it with HV will be satisfactory. I'll post photos and updates of my progress with this project.

Thanks again for all the responses.

Steve D