||English penny, 1916. General Post Office. The start of the Easter Rising is generally thought to have commenced with the reading of the ?Proclamation of the Irish Republic? by Patrick Pearse on the steps of Dublin's GPO. The ?O? is struck sideways. I've only seen three other ?GPO? stamps, the two below and a third not in my collection. All are struck on 1916 English Pennies. This coin was bought by the seller at the Dublin Coin Fair in about 2007. Purchased from Michael Kenny / Stepaside, Co. Dublin, Ireland. (Ar. 9, 2018) $7.