A new forum member recently pm'd me wondering where to find KASL around boston, so I wanted to post my answer on the forum to help out anyone else in the area that might be interested.
http://accardifoods.com/ accardi foods in medford kas kasl, caputo, and all trumps....lots of good tomatoes, even some very high end ones in small cans, but you must buy by the case. They advertise that they dont sell to individuals and their prices aren't as good as some of these other places, but if you put together a decent sized order I have found that they dont mind selling to the public at all. I get a bag of flour, a case of tomatoes, paper towels, a case of fancy imported italian sodas or water and they are fine with that. I think they break cases of empire mozzarella, which is the one used at regina and santarpios, so its a good cheese.
http://www.costasprov.com/ costas provisions also sells to the public, and have a cash and carry window. They have a great cheese that they break cases of called vantaggio... its used at johnny's in mt. vernon, and is a little sharper than empire. They don't have an online product listing, but they carry most major flours too. All trumps, full strength, Rex royal (a non bromated flour recommended by tom lehmann) maybe even harvest king and KASL. They will sell cases of good tomatoes. The nice thing about buying here is that they are set up for small operations and dont mind selling you a single case of tomatoes, or one block of cheese. This is one of, if not the only place in boston that will sell you grande mozzarella, but im not sure if they will break cases. You can call and ask any questions and find out prices over the phone before you go.
If your looking for non bromated all trumps you will need to drive to new bedford or fall river and go to
http://www.rfsdelivers.com/ they have two cash and carry locations with lots of products already there, but you have to call ahead to order (cases only) of grande mozzarella or the non bromated all trumps. They will bring them over from the warehouse if you special order a day in advance. This is another place that doesn't mind sitting on the phone with you to go through their massive catalog.
harvest king flour (one of the best if not the best for long slow fermentations...the flour at apizza scholls and varasanos) is at perkins in taunton, and they have an online product guide.
http://www.perkins1.com/ they have a cash and carry store, so they are happy to sell just one thing and are open to the public. They have a small but nicely thought out selection of single cans of some really great italian and california tomatoes out to buy, along with lots of kitchen supplies. This is where I buy cases of buffalo mozzarella for 63 bucks, but they also have some nice dry cheeses to try and will usually break cases if you just ask them to (not on the buffala).
finally,
http://www.restaurantdepot.com/ is where I shop the most. They have EVERYTHING at great wholesale prices, and they will give you a day pass if you ask. to get a real full time membership all you need is a tax id number, so I have heard of people forming a corporation just to get a membership. I use a tax id for a recording studio, and they dont seem to care that its not food related. This is where I go for screens,peels, cambro containers, pans, pizza cutters, kinves, steaks, sabbrett hot dogs, fresh organic basil, cheesecake, a great 00 flour thats very comparable to caputo, grass fed beef tenderloins, gyro bread, Idy, fresh yeast....the list of good stuff here goes on and on. Most of the stuff here is broken down into single containers as well as by the case, including EVERY tomato under the sun. Its nice to be able to try one can at a time, and this is one of the very few places selling 6 in 1's. I love the polyo mozzarella here as well as the saputo mozzarella (a new product that has been the best tasting/melting aged mozzarella I have found locally, but I also recently got a bad batch that burned easily so the jurys still out), there are many other choices of fresh and aged cheese (belgioioso, 1960, supremo italiano etc) . They have logs of fresh but not in water (cryovac) polyo (another new product).... this is what is used at patsys harlem, and they even sell mozzarella curd. what they dont have is harvest king, buffalo mozzarella, grande cheese, or non bromated all trumps.