Carter and Jasper Authentic Mercantile is a step out of the ordinary as far as reenacting goes. They're not your typical sutler that does the usual uniforms and gear -- they do sundries, stuff you usually don't find at any sutlery.
They do sell some clothing, but it seems that the strength of Carter and Jasper are the authentic canned goods they have for sale. This section alone is worth checking out. The pricing seems very reasonable too.