Ever heard of "hanko" or "inken" ?

In Japan, you have to possess a little seal that you will to "sign" a document in exemple if you want to open a bank account, get a flat, etc... This is used as a signature. In some places a "regular" signature is accepted for "gaijin" (foreigners). It is possible to by them all finished in "hanko-stores" or you can get some more personalized ones. So right now I'm trying to design my "hanko". It is quite fun to do. This is a object that is possessed a lifetime. So I have transcript my last name into "katakana" (Japanese alphabet for non-japanese words). My name is now "オリバ−　フランツ" (oribaa furantsu)
Most poeple possess two "hankos", one for every day paperwork and a second one for very official situation. The second one has to registered and is stored in a safe.
Well, I guess I need just the first one for now...