Largevastinc is the company that sold them. Totally mass produced.

Cost quite a bit: about 54$ canadian bucks with 9$ of taxes and 9$ of shipping, in US dollars. For two self inking stamps of cats: total code for my future enveloppes. These cats stamps will be the official sceal fo all of Lilou's  airmail correspondence. Every single letter shall be stamped with this sceal.