These are handmade signature seals. The reversed characters were handwritten with a brush, not transferred, so no two impressions will be exactly alike. I've made many "cat" and "rabbit" seals in the past, but I've never been able to make the same one twice. There is no seal script for kana characters, but I use variant kana characters to create them. Please let me know your general request in the comments, and I will ask for details on the transaction screen.