Tom, not sure if you found anything, but if you are handy with a soldering iron, all you really need is a good 4PDT switch. Outputs are connected to the wiper and inputs to LP1 and LP2. I've got a bunch of good TACOS 4PDT switches I bought last year - send me a PM with your address, and I'll mail you a couple.
Cheers, Don Bingaman
