I don't think you'll get an authorized Hirsch dealership to do it. I've seen at least 2 or 3 folks with their "signature" say "9-4X Aero Hirsch" ... whether they are USA or not, I do not know. I will see if I can spot them again for you.
How about our Russian friend? Isn't his Hirsched? I know that's Russia and not the USA, but maybe he can tell you if it was a legit Hirsch tune?