family crests for kimono?

I am an American living in Japan, and I absolutely LOVE kimonos. I have several and I'm looking to add a formal kimono to my collection, however, I do not have a Japanese family crest (well... duh). What would be the appropriate course of action? Design my own family crest? Ask around for any defunct or extinct family crests? Simply not wear family crests on my formal kimono?

Please don't answer unless you have a knowledge of kimonos and Japanese tradition.