If you can't source one singly.. and as I live in the UK I can't go to my local electronics shop and buy 120v mains stuff..you should be able to make one.. from individual components http://www.dong-il.net/board/img/cr_multiple.pdf but it may be a little hard to source a suitable spark gap.. I would use a sg rated at 400v (old tv A1 component possibly?) A nice beefy 2.5 meg resistor.. about 1w or similar.. and a disk capacitor in the 470pf range.
I'm assuming this part is across the mains input.. probably before the switch, and was killed by lightning strikes nearby?
Try a few online component suppliers. I googled the part and found quite a few places that say they have them. they all want to reply with a quote by e,ail... so I can go no further. I'm guessing 500v on the SG but that relates to uk 240v mains.. I'm sure any similar rated component from radio shack will do.
I wonder if the ARRL might not be a better starting point?
Haven't seen a varistor in years :) Last one I remember seeing was a nasty 4" long thing in the KB vc53 tv. Full of asbestos and selenium.. big health hazard.
I would think that any component that does the same job will do. (goes to google surge protectors) after much searching... a uk device.
I can't find a usa 120v one.. the sites are unfamiliar. I bet you can tho :)
Philips are often quite helpful.. You could try contacting their local service station and see if they can help. I have had them pop odd components in the mail once or twice over the years.
