Alternatively try to find a person who can make japanese labels in Cali, i heard you guys have the Japan American southern california society over there.
Japan America Society of Southern California - Home. Maby you can just make the labels in America with some japanese help so you can oversee the process, put the labels in boxes, ship them to japan , and let the collegues in Japan label the hoodies? Its an alternative plan but it might be better if you are in more control.