Rather than being "remainders", or "left overs", these are CTO (cancelled to order) by the Post Office from the get-go. Most "used" stamps from all the communist countries were CTO for the collectors market & were sold for virtually pennies at the time. The communists realised the value of stamps as propaganda tools & so made them readily accessible to even school children on limited budgets.
As your photo shows, they were cancelled in sheets after printing so you get the situation where a stamp looks as if it has been used but still has gum on the back. Unfortunately the two stamps you show are extremely common, single stamps are unsaleable, so I'd guess you'd only get a buck or two for the sheets.
The Lenin stamp comes from a set of two issued in 1952 to commemorate Polish-Soviet friendship, Scott catalogue #B93-B94. Both stamps feature the same portrait of Lenin with his name engraved in the lower left corner. However, there is a variety without his name which was discovered in CTO packets of stamps for collectors. The theory is that this was an initial unapproved print that somehow got into the CTO process & passed through unnoticed. There must have been a fair number of them as they only sell for about $20 each. Unused examples are unknown so it's surmised that the whole print was CTO'd
