Spanish Viceroys of Peru - postage stamps, Mint never hinged, Peru

These mint postage stamps, printed together in a block of four, were published on the subject of “Spanish Viceroys of Peru”. The stamps show: 7.80 S, José Antonio de Mendoza Caamaño y Sotomayor (1667-1746); 7.80 S, José Antonie Manso de Velasco (1689-1767); 7.80 S, Manuel de Amat y Junient (1704-1782); 7.80 S, Mauel de Guirior (1708-1788).