Like Ris said, check out Higginson's Powders but it's best to shop online and email, fax, or call your order in a day or two ahead of time. If there's no powder or primers in the order, then shipping is quick and cheap. If there is powder and / primers, the shippers have a hazmat fee. That's when I choose to go for a Saturday morning drive and get it myself.
Other that, LeBaron is about the only other game in town. The suits at Sail are absolutely against getting into reloading gear and components. I tend not to shop there. Oh, and the Stittsville range has a limited selection of bullets and they sell some gear. But they say they can order whatever you want.