I've also located a potential source of General Mills "All Trumps" flour in Queens, but I still need to see if they'll sell to the public. The place is called Zahner's Cash and Carry, and it's located about 1 block off the BQE at 6235 30th Ave in Woodside, Queens. I visited there about two weeks ago but arrived just as they were closing, so I only had enough time to check the flour aisle and see that they carry All Trumps in 50lb bags for under $20.
I made it back to Zahner's Cash & Carry today and noticed something I missed on my first trip -- their exterior sign clearly says "Open to Public," so you shouldn't have any trouble buying there.
They had All Trumps in stock for $18.95 per 50-pound bag. They also had another hi-gluten flour in stock: Bay State Millings' "Perfect Diamond" flour. BSM's website describes it as "Premium-grade high protein spring wheat flour." Suggested uses include: Buns, hard rolls, deep dish pizza, French and Italian hearth breads, specialty breads. I didn't think to check if Perfect Diamond is malted, but the label definitely indicated that it's bleached and bromated. Zahner's has it in 50-pound bags but no price was posted.
I checked their selection of cheeses, tomatoes and pizza sauces but didn't find anything that interested me. They did have Stanislaus Full Red pizza sauce if you happen to be looking for it, but they only carry it in #10 cans. It appeared to me that they'll let you break a case (i.e., they had prices posted both for cases and for individual cans), but it would probably be a good idea to ask before cracking open a case to buy a single can.
If you're thinking about checking them out, here are some directions: Approaching from Brooklyn, they're located right off exit 43 from the BQE. Just take a right at the bottom of the exit ramp and their warehouse is down about 1/2 block on the left. They're open on Saturdays until 1:00 pm.