This was apparently received as a souvenir from a trip to Okinawa. "Ryukyu stamps" are stamps issued in Okinawa, which was occupied by the U.S. military in 1945, and are also known as "Okinawa stamps." How about adding them to your collection? Although they are unused, there are stains and tears/dirt on the outer vinyl due to long-term storage. Please check the photos. These are items stored by an individual. We appreciate your understanding and purchase.