The stamp - designed more in hope than expectation - shows Scotland's triumphant players lifting the trophy in 1978.
The artwork was created so the stamp could be released to the public in the event of Ally McLeod's team winning the tournament in Argentina.
But the squad's failure to make it past the group stages after a humbling defeat to Peru and a draw with Iran meant the stamp was shelved forever.
Now it is lined up as one of the rare treasures and curiosities to be put on display this summer at the Post Office museum in London.
The Royal Mail commissioned two stamps - an 11 pence First Class and a Second Class costing nine pence - and the artwork was completed before the tournament.
The plan, dependent upon Scotland winning the tournament, was to issue both into circulation within a month of the victorious squad's return from South America.
At that time rules banned anyone living, other than members of the Royal Family, from having their true likeness on a stamp, so the players had to be shown as artist's impressions.
The Scotland stamp shows captain Bruce Rioch holding the trophy aloft, while players purportedly bearing to be goal heroes Archie Gemmell and Kenny Dalglish punch the air in the background.
The proposed stamp was briefly displayed in Glasgow in 2000 but has not been seen in public since and has come to light in the wake of a debate in Parliament.
Along with telegrams from the Titanic on the night it sank, and a sheet of stamps depicting an ageing Edward VII, the Scotland stamp will go on display at The British Postal Museum and Archive.
Drawing up plans for the stamp, while wildly hopeful, reflected the optimisitc mood in the country at the time.
The national team boasted many quality players and the squad headed to South America with the song Ally's Tartan Army boasting that they were off to win the World Cup.
But the campaign was a disaster with poor results and winger Willie Johnston being sent home for taking a banned stimulant.
One of the images that stuck in the memory was the manager Ally McLeod sitting in the dugout with his head in his hands.
The Scotland World Cup Winners stamp can be found at the Clerkenwell museum under the category of Stamps That Never Were.
The museum complex is at the centre of a £22 million fundraising bid to revamp its exhibition by 2016.
Part of the revamp will include unveiling a secret underground railway which was used to transport mail across London.
Islington South and Finsbury MP Emily Thornberry said the funding would allow the museum to put its full archive of material on display for the first time.