On November 1, 2018 Ireland issued a stamp commemorating the 50th anniversary of Na Piobairi Uilleann
, or The Uilleann Pipers , an Irish, non-profit organization dedicated to the promotion of the Irish Uilleann Pipes, or Irish bagpipes and its music.
a computer-vended stamp of the same design was also issued in 2018. I can find no source describing the source of the image used on these stamps. It is definitely an old Irish manuscript, perhaps the Book of Kells.
Also shown is an earlier Irish stamp (Sc #485) from 1980 which gives a better view of the Uilleann Pipes.
From Wikipedia, The Uilleann Pipes are distinguished from many other forms of bagpipes by their tone and wide range of notes - the chanter has a range of two full octaves, including sharps and flats - together with the unique blend of chanter, drones, and regulators."