The Big Dippers are reckoned to have AV-magnets. They have a scooped midrange as you know. The PAT Pend 63 comes close to these, I think. So are the Mothers Milk's. You can ask the BKP-team for advice/information.
I have to stress that the Fender John Mayer strat sounds good (tested one) into amps with a bold midrange. Like a Bassmann and other tweedamps. For me personally, rahter thin into a Deluxe 22. So the amp contributes a lot to the John Mayor-sound (who plays expensive Two Rock-amps), but I guess you know all this.
