Niue

1981 Easter, IMPERFORATE Set of 3, M/S & Set of 3 M/S’s

Topic: Art, Paintings by El Greco, Gallego & de Ponttormo

Singles from left margin of sheet

On white gummed paper, Mint Never Hinged

Stanley Gibbons Catalogue: #425-7, MS428 & MS429

Plate Proofs or Imperforate are not listed

I believe these to be Plate Proofs. The printer of this stamp issue Fournier S.A sold its philatelic archives of stamp artwork and proofs in 2007 through the German stamp dealer and auction house Gärtner.