The cargo ship SS Politician, which had 28,000 cases of whisky, sank off Eriskay in Western Isles 75 years ago.
Eight bottles of the whisky were recovered by a diver in 1987.
The National Trust for Scotland (NTS) has suggested that two bottles it has on the Isle of Canna could be added to these eight known bottles.
The bottles in the care of NTS are kept at Canna House and belonged the late John Lorne-Campbell and his wife Margaret Faye-Shaw, who gifted the property and Hebridean island to the trust.
Fiona McKenzie, archivist at Canna House, said: "According to the previous archivist, the bottles have 'always been at the house'.
"She was here from the 1960s and that's well before the diver brought up eight bottles in 1987. So looks like we may have two bottles that are not included in the official stats."
Many other bottles were salvaged from the SS Politician at the time of its sinking in 1941 and still thought to survive, but have not been officially recorded.
Hundreds of cases of whisky were hidden from customs officers by islanders. Some locations of these secret stashes have since been forgotten, according to islanders today.
The SS Politician was headed for Jamaica when it ran aground on the northern side of Eriskay in bad weather.
Scottish author Compton Mackenzie, published the novel Whisky Galore in 1947, which was loosely based on the shipwreck.
It was adapted for the cinema in a 1949 Ealing comedy.

Carwyn Jones said Wales had a "proud tradition of being a friendly and hospitable nation".
"The message of peace and hope is particularly poignant this year," he said, referring to the terrorist attacks in Tunisia and Paris.
About 50 refugees from Syria have been re-settled in Wales with more to come.
Torfaen, Ceredigion, Neath Port Talbot and Caerphilly have been the first councils to welcome refugees, with more to be dispersed to other areas in the new year.
In his seasonal message to the nation, Mr Jones said:  "At Christmas, it's more important than ever that we spread the message of togetherness and unity in our Welsh communities.
"We have a proud tradition of being a friendly and hospitable nation.
"As fifty Syrian refugees make their home in Wales, they will be experiencing their first festive season in the UK - I'm sure they'll get a warm Welsh welcome and we wish them well in their new lives."
The first minister also asked people to "spare a thought" for those working over Christmas - such as the emergency services, medical professionals, charities, care workers and the armed forces - who "all deserve our thanks".
"They work tirelessly while we enjoy ourselves," he said.

13 April 2016 Last updated at 20:41 BST
She told BBC TV's Ask the Leader election special it had been a "terrible mistake" for the Lib Dems to make "a promise which we could not keep" while part of the coalition government at Westminster.
The Welsh Lib Dems want to replace tuition fee subsidies of up to Â£5,190 a year with maintenance grants of Â£2,500.
Ms Williams said she wanted to be "upfront" about what she thought was affordable.
Two bottles of whisky recovered from a shipwreck that inspired the book Whisky Galore may have been missed from official statistics.
[NEXT_CONCEPT]
Syrian refugees facing their first Christmas in Wales are sure to get a "warm Welsh welcome", the first minister has said.
[NEXT_CONCEPT]
Welsh Lib Dem leader Kirsty Williams has asked voters to trust the party's pledges on student grants despite broken promises not to raise tuition fees in England.