We have a local Irish shop (Paddy's on the Square) that stocks Celtic music cds, and the majority of their stock is older albums -- I know I've seen Seven Nations (picked up a few of their older cds on clearance) and the Glengarry Bhoys there. Perhaps try an Irish specialty shop?
"There are worlds out there where the sky is burning, and the sea is asleep, and the rivers dream. People made of smoke and cities made of song. Somewhere there's danger, somewhere there's injustice, somewhere else the tea's getting cold. Come on, Ace; we've got work to do!"--Doctor Who, "Survival"