Just for the record and briefly to get this in before the site goes down again:

Brian O'Rourke in 'Pale Rainbow' has some remarks on An Caísideach Bán. As well as a detailed notation of the air (from Seán 'ac Donncha's singing), the words and his own translation.
Among many other things, he refers to a Tory island version 'An Gaiscíoch Bán'.

Anyhow, I have a version of the air Séamus Ennis played (he was recorded playing it during the late 1940s at a concert in Ennis), which, if I remember correctly, he got from a man called McNamara who was resident of the Ennis workhouse. The meeting between collector and singer are documented in Ennis' collector's field diary 'Mise an fear ceoil' or Going to the well for water, depending on your language of choice for reading the book.