The Peeler and the Goat is on the DT (with "Penshaw" instead of "Banba"). An Gabhar Bán does have the same air and is about a drunk and disorderly goat. It's to be found on an unofficial Clannad website (www.jtwinc.com/clannad/clanhome.htm), but there are errors - expert Irish speakers are welcome to contact the site and give corrections - also to add to the Gabhar Bán thread started by Áine at Mudcat.I still have no info. on any related but earlier song about recruiting sergeants.
Thanks Martin, Mick and Parable for the information and lyrics you've contributed. Mick - who was Seamus O'Farrell, i.e. what else do you know about him?