I bought a wreck off eBay in about 2008 and Nick Regan refurbed it. not seen another one. used to pop up at POA shows back in the day . Williams early SS seem to be very common or never seen. the common being BK JL Gorgar Flash and Firepower. they were far less reliable than Bally so "bit the dust "so to speak a lot earlier in their working lives.
also consider hunting a Laser Cue as virtually a copy!