David McDonald gets the most mentions: Japanese Swords, Antique swords, WWII swords, Tsuka-maki, Translations, Restoration, Sell, Buy (montanairon.com)   Chris Lohman also advertises the craft.  Don't recall hearing any word-of-mouth on his work: Japanese Sword Restoration Parts & Supplies - Fred Lohman Company (Japanese-swords.com)   There are probably more.