Solid state voltage limiters are available on Ebay. They go for about $50.00. Homemade solid state VL can be made from Radio Shack parts for about $3.50 and an hours time.
Plenty of information available on the FABO, FBBO, and FMJO forums if you search for it. There is no real fix to a bad one. You can take them apart and clean the contacts but, I've not seen that last very long.
