Bidspirit auction | Worldwide Air Post Stamps and

Worldwide Air Post Stamps and Postal History - Portuguese Colonies - India - 1939-40, New York World's Fair, double green overprint on 4½t ultra, excellent centering and post office fresh, full OG, NH, VF and very rare, only 25 stamps were printed, Sanabria and Kessler guarantees, a common stamp with red overprint (1900 printed) is included (LH), Est. $3,000-$4,000, Scott #C4 footnote, var