The souvenir sheet (S/S) issued by Korea on June 13, 1966 is one of the most unusual Korean stamps in my opinion, in that it has been issued to commemorate an event. I have a little background information that I am putting into this article, but I hope that some reader may enlighten us with some more information on why this S/S was issued, especially in the way it was printed. It would seem that by overprinting the unissued old sheets the Korean government would not save a lot of money, but maybe saving money was indeed the reason? See Figure 1 for a photo of the S/S.

As stated in the article posted in the KP Volume 15 No.3 (August 1966; see Figure 2), this S/S was only issued with the overprint, on what was apparently an old printing of S/S’s that had not been issued in 1961. In addition, whereas almost all other Korean souvenir sheets are issued with the normal issue of the same design, there was no single stamp issued to commemorate the 6th Postal Week.

The Scott number for this S/S is 534 and valued at $4.00. There is a note saying that No. 534 was not issued without a surcharge and there is no listing for one without the surcharge. The Korean Postage Stamp Catalogue (KPSC) number is 391 and it is valued at 5,000 won ($4.50).

The KPSC does list the 391a with the script 가쇄빠짐, meaning the overprint is omitted, and values it at 3,000,000 won ($2,680), showing it is very rare. By some means, a few of the ones without the overprint “escaped”. See Figure 3 for a photo of one without the overprint.
This sheet was originally issued in 1961 for 5th postal week. See Scott 283(1958)/291B(1959)/313(1960).
However, for some reasons this event was probably halted or canceled. So this s/s became unissued.
5 years later, South Korea again held the event of 6th postal week and this sheet was overprinted to commemorate it.