Bidspirit auction | Worldwide Air Post Stamps and

Worldwide Air Post Stamps and Postal History - Canada - 1929, Commercial Airways, Ltd., ''VIA AIR'', imperforate trial color proofs of (10c) in green, light carmine, yellow and orange, each one has bottom right corner margin, printed on thin white card, no gum as issued, NH, VF, Unitrade #CL47ii, C.v. CAD$1,200, Est. $300-$350, Scott #CL47