Bankbooks (Am.) or passbooks (Br.), 통장 in Korean, were once common in Europe and North America, but these days they are rarely used by banks. In Korea they are still, even today, in use. Of course Koreans use “plastic” as much as anyone, probably even more than most nations, but with a bank account you will still get a bankbook. And in Korea that means paying 100 won for the privilege. In modern bankbooks this is now printed already in the bank book, as a prepaid revenue stamp. However, until approx. 10 years ago (and sometimes even more recent than that) revenue stamps were used to pay the 100 won. Mind you, during the final years of revenue stamp usage 100 won was worth a mere 10 dollar cents.
Bankbooks of the seventies used to look like this: a small booklet, which could easily fit in a wallet or a coat pocket.
This bankbook is a 가계예금통장 (household savings bankbook) and was issued by 서울은행 (Seoul Bank) in 1976. This bank is now part of KEB.
The exact issue date can be seen several times on this page of the book: 11 August 1976. At that time the cost was still 30 won, later it became 50 won and after that 100 won.
The 30 won stamp is listed in the 2003 and 2015-2016 editions of the ” Korean Postage Stamp Catalogue” as RP73. Oddly enough it is listed with an issue date of 1 April 1977, which is unlikely given the date in this bank book.