The discovery was made at Port Logan beach on the south-west Scotland shoreline on November 22, 2006.
Glasgow Caledonian University's (GCU) Scottish Cold Case Unit has been working to establish the woman's identity.
They now believe she may have entered water in the Dublin Bay area at least 16 years ago..
This is based on tidal flows, the weather and the location of where the body was found, which was the filming location for the BBC’s hit drama Two Thousand Acres of Sky.
The woman is thought to have been in the water for up to six months, so may have gone missing in the spring or summer of 2006.
Forensic work has indicated that she was aged between 30 and 50, was of thin build, and between 4ft 11in and 5ft 4in tall.
She was wearing size 10 black Bay Trading trousers, a white BHS size 34C bra and tan-coloured tights.
Tidal movements in the area are complex with some bodies which enter the water off the east coast of Ireland and in Welsh waters washing up on Wigtownshire beaches, while others are discovered in Lancashire.
An updated facial reconstruction image of "Port Logan Woman" was produced last year.
Dr Maureen Taylor, co-director of the Scottish Cold Case Unit at GCU, said: "The team have been undertaking a number of inquiries around the clothing she was wearing, a geographical profile of the location she was found, sea and air incidents and missing women from the UK and Ireland.
"Although she was found in south-west Scotland, it may be that she had lived in, spent time in, or had travelled to or from Ireland.
"Is there a friend or relative that you haven't heard from or lost contact with who may have gone missing in the spring or summer of 2006? Is there someone who used to come to your place of work or leisure activities that you no longer see?"
Dr Taylor added: "We hope the facial reconstruction jogs someone's memory and adds more pieces of the puzzle as to who she might be."