"I'm really happy for the guy who bought the ticket," joked Chris Loranger, the former director of Presentation House Gallery, in an interview with The Early Edition.
The black-and-white photograph is one of two Richard Avedon prints purchased by Loranger in 1983 for $2,000 apiece, in a bid to secure an exhibit by the famed celebrity photographer.
Loranger then raffled off the shots for the $5 price of admission.
Loranger says the winner was a neighbour of his, and he believes he's the same person now auctioning the print at Vancouver's Maynard's Fine Art and Antiques.
Image depicts Monroe's 'sad' side
Kate Bellringer, the director of contemporary and Canadian art at Maynard's, says the image is unique because it captures a candid and vulnerable side of Monroe.
"It's sort of unlike what we would normally see Marilyn as," said Bellringer.
"She's not quite the breathy blonde. She looks a little bit more sad, actually, and tired."
The gelatin silver print was taken in 1957 in New York City, and is signed by the late photographer.
"She had come to Richard's studio to be photographed and had danced and posed and done Marilyn for hours," said Bellringer.
"This photograph was taken sort of at the end of shoot when she was basically just taking a moment to herself."
Similar print netted more than $80K
The print up for auction Wednesday is one of 25.
Another in the same edition sold for over $80,000 in 2011.
Despite its incredible jump in value, Loranger has no second thoughts about raffling off the portrait in 1983.
"You can't look back with regret," he said, explaining that securing a Richard Avedon show was a huge coup for his gallery.
"It worked out really well I think. We got what we wanted, and one guy got a great prize."