GRENADA SG163c 10s slate-blue and bright carmine narrow frame perf 12 Fake Pmk

1938-50 10s slate-blue and bright carmine wet printing with narrow frame perf 12 very fine used appearance but with light part strike of Madame Joseph forged cds dated 21 AU 42 (type 205). Only 780 issued in this perforation. Purchased from Stanley Gibbons (still on their card)