...and over NINE YEARS LATER, I'm still among the many who are looking for dual rotary, concentric-shaft 500k pots with a push/pull on/on DPDT. It's for an electric guitar.
Terminology: "Concentric-shaft" pots means, to me, that there each rotary pot has its own control shaft, one of the shafts being inside the outer, hollow shaft. Two concentric knobs would be needed, and each pot would be turned independently of the other. This is as opposed to "ganged", wherein a single shaft controls all the pots, which are turned at the same time, and are always in the same position as one another.
The Close but no cigar gallery:
Bourns PDB183-GTR21, a ganged dual pot with push/pull on/on dpdt;
Bourns PTJ90 2, a concentric* pair of pots with a push/push on/on SPDT;
More controls wanted
I also want a "Blend pot" like Bourns PDB182-GTRB, but with the addition of a push/pull on/on DPDT
More and more electric guitar players are being introduced to the idea of custom wiring in their instruments; I predict that demand for controls like the ones I've wish-listed above is about to explode. I hope the supply arrives soon!
*In the PTJ90 datasheet on Bourns website, both words "concentric" and "gang" appear; the product fits under "concentric" by my definition, above.