Vanilla Beane is in DC ...
http://thegrio.com/2010/06/15/dorothy-heights-hatmaker-still-going-at-90/
Thanks for the info. This article says that "Beane still works full time at Bene Millinery", so maybe that's a place worth checking out. There is a Google+ page for Bene Millinery & Bridal Supplies (https://plus.google.com/104903460034980826952/) which seems like it would be the place, but there's not much store info on the web, as you said. I guess I'd have to call or stop by, which maybe I can do the next time I'm in that area of DC.