The extremely astute Nancy Friedman suggests looking into stockist, noting “US companies are appropriating this BrE term… Until recently, the more-common term would have been ‘where to buy’ or ‘retailers.’” Never even once having come across this term, I would have doubted her, had she not supplied four web sites that list the stockists from which one can purchase their stuff:
http://www.rgbcosmetics.com/stockists.php
http://mishkanyc.com/stockists
http://www.billykirk.com/stockist/
http://www.remedyquarterly.com/about/stockists/
Nancy notes that Remedy Quarterly, a magazine, is based in Brooklyn.
I am now convinced that stockist is indeed happening in the U.S. However, it has not yet appeared in the mainstream media, only, apparently, in commercial communication. This puts it in the same category as bespoke: a phony, hype-y word that exists–and one hopes will stay–in the realm of advertising and promotion.
notoneoffbritishisms.com 
Our programmers over in the UK use “bespoke” on a regular basis in relation to system output — “in addition to what came out of the box, we had to support several bespoke reports that the client has used for a number of years.”
American here….bespoke was pretty commonly used in Boston in the 1960s when I was growing up. Not sure how common it is now, but possibly common enough that I stopped noticting it.
I really like “stockist” and as of today, I’ll be using it when appropriate. 🙂