https://wholegrainscouncil.org/find-whole-grains/mail-order-grain-sources
http://www.thewondermill.com/
"Capacity, Power & Versatility
The WonderMill Electric Grain Mill has the capacity to perform big jobs. You can grind over 100 pounds of flour in an hour. You don't have to worry about overloading The WonderMill because of its LARGE 1250 WATT LG ELECTRONICS MOTOR. It is indeed the most powerful micronizing mills available. The WonderMill will not only grind wheat, corn, rice, and other small grains like Quinoa and Amaranth, but it will also grind legumes and beans. Go to willitgrind.com to see the large list of what The WonderMill can grind. Those who use the WonderMill for commercial applications (not under warranty) have found the WonderMill to be very durable and long lasting. Donna Poelstra's business uses a WonderMill wheat grinder to grind 100 to 200 pounds of wheat a week, and she has been using the same grain mill for over 2 years to do it. Many others use the WonderMill to grind fresh whole wheat flour at farmers markets (like Castor River Farm), running large quantities through the WonderMill throughout the day. Though the WonderMill is not a commercial grain mill it holds up well to the commercial challenge, and it will give you that same reliability in your home."
https://grainplacefoods.com/ located east of Grand Island NE .
They offer larger sizes. Cant tell you about the shipping charges.