This is a wee gem which has been hiding in plain sight for nearly 50 years. I bought Breandan Breathnach’s "Ceol Rince na hEireann Vol. 1" around 1972, the year my brother and I persuaded our parents that the holiday we wanted that year involved the Cambridge Folk Festival, where I found the book on sale. Although I didn’t read a note of music at the time, I could see that it could be useful as a reference, as I recognised several of the tune titles and it’s been an excellent source and reminder for all those years.
I realised a week or so ago that there were still a few tunes in it which I had never looked at, and found this fine 3-part reel, Breathnach’s source was given as fiddler Tommy Potts. I have never heard it played or recorded anywhere, and a "Google" search was only able to come up with 2 female fiddlers playing it on a "Youtube" video, I think on the "Na Piobairi Uilleann" website, but I can’t find it again to link it. Their source was also Breathnach’s book, but they had no further information on the tune apart from that.
Played "singly" without repeating the parts, it has echoes of the "Colonel Fraser / Dublin Lads" type of reels in Gmaj.