We received Moutarde Aux Trois Poivres by Epicerie de Provence from a friend in France. Need a source in the Untied States for this wonderful mustard.

I heard Pommery Meaux Mustard recommended on the Splendid Table podcast, which you can get on Amazon!

They have a Facebook page, and while they don't seem to answer questions posted there, perhaps you can contact them via their website to see who they distribute their products through (even amazon has some of their stuff, although not mustards).