Don't know where you're located in Montana 50Cal, but if you're anywhere near Miles City you can buy it a lot cheaper directly from the GOEX distributor there.

Western Powders, Inc. (black powder only)
P. O. Box 158
Top of Yellowstone Hill
Miles City, MT 59301
800-497-1007, 406-232-0422
Fax: 406-232-0430

The closest distributor to me is about 150 miles away. But he will bring my powder order and meet me closer to my home when he travels in my direction.