The last series of Korean revenue stamps to be issued for the whole of Korea was this series of 10 revenue stamps. They were printed by KOMSCO, the official government printing company which also prints Korean banknotes and postal stamps. The series was according to the official KOMSCO website put into circulation in 2005. They were however introduced a year earlier in ordinances.
The complete series has values ranging from 100 won to 30.000 won, with a 50 won value introduced in 2007. The complete series is shown on the KOMSCO website with this image:
(Copyright: KOMSCO.) The Korean text 견본 means sample or specimen.
The stamps were introduced in an ordinance published in 2004. The actual images were not shown, but such things as the sizes of the stamps were introduced.
(Image from 제15743호 2004. 7. 13. (화), page 3: 대통령령제18470호 (수입인지에관한법률시행령중개정령), see the Ministry of Information website for more examples.)
This document shows the sizes of the different stamps. Effectively all values other than the 30.000 won value are 27mm x 30mm in size, while the 30.000 won value is 32mm x 30mm. Higher values might have been planned (references to 50.000 won and even 100.000 won values can be found in other documents), but in practice this was overtaken by the use of 전자수입인지 (“digital revenue stamps”). All 종이수입인지 (“paper revenue stamps”) were discontinued on 1 Januari 2017.
Below are two examples of usage of these stamps which could still be seen at the National Archive of Korea as late as October 2016. The examples are from 2011/2012 but the pictures were taken from random page shown by NAK staff to me at the NAK Daejeon location in that month. (There are no personal details visible in these pictures!)
This form was used to request copies of NAK documents, including payment for those copies. Here a document with a total value of 136.300 won:
A slight smaller amount of money was stuck to this form:
Notice that the 50 won stamp is not the new 50 won value (with the dinosaur on it) but the old stamp from the 1970s!
At NAK Daejeon they could even still sell me some of the stamps (the 100 won value in particular), but I was not allowed to buy a whole sheet of 100 won stamps. That was effectively the last chance for me, a few months later it was all over.