Bidspirit auction | Latvia - Air Post stamps

Latvia - Air Post stamps and covers - Selection of Air Post Issues: 1921-33, 12 complete sets, starting with Bleriot XI issues, then Semi-Postal Air Post items - Eagle, Aviation Pioneers and two imperforated sets of Biplane with upright and sideways watermark, full OG (three stamps with toned gum), NH, VF, C.v. $925, Est. $300-$350 (website photo), Sc. #C1-8, CB3‑13, a CB18a- 20a