Northern Rhodesia Postage Due 1929 Receiving Authority Specimen

POSTAGE DUES: 1929-52 RECEIVING AUTHORITY SPECIMENS: 2d &3d values VF/M perf SPECIMEN and further handstamped "Especimen" in green. Rare pair. These specimens emanate from a Portuguese Colonial receiving authority. The additional handstamped defacement was applied in Lisbon prior to distribution of the specimens (received through the UPU) to the overseas Portuguese colonies. Probably from the Angolan archive in this instance.