Anyway, the USA address is: Mephisto -- 1037 Segovia Circle, Placentia, CA, 92870. Tel. 714.632.2570.
I bought my two pair in Toronto, and the salesman was very helpful. He seemed to think that my own orthotics should be put in the shoes whenever possible (obviously, not in sandals), but I like to change my shoes throughout the day. After wearing the orthotics for several hours, I need a change. The orthotics are very hard plastic. Are all custom orthotics like that?
Anyway, if you want the address for other countries, just ask. They are on the catalogue I got from the store.