Kevin from Goodrich told me the only other one of these he's ever seen was at the Buddy Emmons' estate sale.
Combination Matchbox, Steel Driver and Matchbro all in one, use it as a tone control, or bypass the whole shooting match. Kevin from Goodrich went over it recently and said it's working like it should.
Slight volume increase when in Matchbro mode, but that's the way it was designed.
$320.00 shipped in the US of A