Claire, the CD I have is a Gael Linn CD, issued in 1991, with the lyrics! It is still available from the two outlets I mentioned above. I didn't realize there was a reissue through Shanachie.
If you like Mairead's singing, you may also enjoy Aoife Ni Fhearraigh, also from Donegal with a similar sounding/quality voice (though a bit more breathy-Brennan sister sounding, if you know what I mean). You might also be interested in getting a CD of Donegal singers called "Seoda: Sean-Nos as Tir Chonail" which has 5 songs by Cait Ni Dhomhnaill, one of my favorite Donegal singers. It is available mail ordered from Clo Iar-Chonnachta, and their email is: