Bidspirit auction | Worldwide Air Post Stamps and

Worldwide Air Post Stamps and Postal History - United States - 1998, Space Shuttles, imperforate proofs of $3.20 in magenta and $11.75 in cyan, two sets in left sheet margin vertical pairs, printed on coated and uncoated paper, no gum as issued, NH, VF, C.v. $900 for stamps on uncoated paper, pairs on coated paper are priced with ''-'', Est. $600-$700, Scott #3261-62 Pa, Pb