For philatelists interested in Korean philatelic items the best source of information is probably Kobay. Unfortunately Kobay is available in Korean only and ordering can due to the constraints effectively only be done by Korean nationals. However, seller “jsm654” recently listed several interesting covers which we would like to show to non-Korean speaking philatelists.
The first cover was sent in August 1977 to a recipient in Seoul. It was “franked” with two RP65 revenue stamps, making a total “postage” of 20 won. The postal services didn’t fall for the trick and even refused to cancel the revenue stamps. A total of 40 won postage due was demanded.