If you weren't after DCC w/sound the only one I could recommend without reservation is Kato's C50, something you'd have to buy from Amazon or Feebay.
Otherwise, fuggedaboutit! There just aren't many short wheelbase steamers out there. Bachmann makes a handful but as I'm finding out they're mostly pretty piles o' poo. And after a bad service experience with them I definitely think they should be avoided.
BLI may be our only hope. They don't currently offer anything with something other than a whatever-8-whatever configuration but they seem to be pretty prolific so maybe we'll see something with 6 or less drivers from them in the near future.
be able to find an Atlas Shay left over from the most current release but otherwise....
I've given up on trying to find anything domestic and am looking overseas for options, (Fleischmann, Dapol, etc) but haven't pulled the trigger on anything yet. If I get a good one I'll let ya know!
Hopefully TractionFan or CTValley will jump in here with recommendations-my response pertains only to what is currently on the market; they may be able to recommend older releases we might find on the auction sites...