Italian Colonies - Eritrea - Postage Due stamps

Italian Colonies - Eritrea - Postage Due stamps

1920, 5c orange and magenta, inverted numeral and black overprint ''Colonia Eritrea'', bottom sheet margin block of four, full OG, NH, F/VF and very scarce double error multiple, expertized by Dr. Bolaffi, G. Oliva and others, C.v. $2,200 as hinged singles, Sassone #14a, €6,000 as singles (prorated for NH), Est. $1,000-$1,200, Sc. #J1bc