South West Africa 1924 KGV 2d Setting via Varieties Block

1924 KGV 2d dull purple Setting VIa, 9½mm between ovpt, South West 16½mm (SG 31/CC54).VF/UM/M block of four with varieties JOINED "A" & "F" of "AFRIKA" upper top left stamp and OPEN "O" of "SOUTH" and perfect clear "COLON" after "South West", both varieties upper right stamp. Previously hinged top pair. Fresh, interesting. See additional image below.