I recently bought 10 1-kilo packages of Bel Aria 00 flour from chefswarehouse.com. It was $12.42 plus a flat $12.50 for shipping, or a total of $24.92, for 22 pounds. I had originally wanted to buy some Caputo 00 flour but I couldn't handle 55 pounds. Subsequently, I received a gift of 10 1-kilo bags of the Caputo 00 flour (in the blue bag) from the importer/distributor of the Caputo 00 flour. Now I have over 40 pounds of 00 flour.
Chefswarehouse seems to be best for large quantity/size purchases. In fact, you won't be able to order most items in small quantities. I had good results with the handling of my purchase. I believe the shipping charges are based on dollar value of purchase rather than weight since the overall cost for the Bel Aria 00 flour was less than anywhere else I checked.
I am not surprised about failing to get responses to emails sent to PennMac. I experienced the same result when I first tried to email PennMac about a prospective purchase. As pftaylor says, the best thing is to just call Rose. I did this when I first called PennMac to talk about Steve's purchase of a bad bag of 00 flour some time ago. Somewhat as a conciliatory gesture, she offered to allow members of the forum to purchase items not listed on the website and, in many cases, at a discount. As for the PennMac website, PennMac has been trying to add items to the website but the task was given to one of the sons of the owner, a college student with too little time to really devote to the assignment. However, having a copy of a document listing all the products offered by PennMac, I can assure you that they are a big factor in the pizza supply business in the PA region, offering far more items than listed on their website. If in doubt about a particular item, the best thing is to call Rose and ask her. It may be useful to mention the forum, but I wouldn't talk about the Steelers just yet.
Peter