Bidspirit auction | Soviet Union Stamps of 1924-40

Soviet Union Stamps of 1924-40 - 1927, inverted and strongly shifted to the top black surcharge (type II) 8k on Postage Due stamp of 2k violet, typo printing on gray (!) paper, vertical pair, nicely centered, full OG, NH, VF and a spectacular and unusual item, each stamp with Soviet Philatelic guarantees, Est. $800-$1,000, Sc. #360 var