In Eilis Brady's comprehensive book on Irish children's games, All In! All In!, she gives this for One Two Three O'Leary:

My mother said,
If she caught me playing with you,
She'd bring me upstairs and give me:

1, 2, 3, O'Leary,
4, 5, 6, O'Leary,
7, 8, 9, O'Leary,
Postman's knock.

Eilis Brady then goes on to write:

Sometimes the first three lines of the above rhyme are omitted altogether or instead of the numbers the following words are used:

1, 2, 3, O'Leary,
I spy Miss O'Leary,
Sitting on her bum O'Leary
Eating chocolate soldiers.

Eilis Brady continues:

The inventiveness of the children in substituting new words to suit new environment is shown in the following version of the above rhyme. The main road to and from the Corporation housing estate in Finglas passes the Merville Dairies where ice cream is made and where many of the tenants also work.

1, 2, 3, O'Leary,
I spy my Auntie Mary
Coming out of Merville Dairy,
Eating chocolate ice cream.

(Elis Brady is described in the 1975 book published by Comhairle Bhéaloideas Éireann, An Coláiste Ollscoile, as a member of staff preparing an Irish-English dictionary in the Department of Education, who has contributed a valuable collection of children's folklore to the Department of Irish Folklore in University College, Dublin. "Her awareness of the similarity between the traditional customs and social attitudes of Gaeltacht people and those of native Dubliners springs from her continued contact with Conamara since childhood. It has helped her to appreciate the importance and urgency of recording the lore and idiom of Dubliners".)

Most unfortunately, she doesn't seem ever to have done a similar book on Gaeltacht children's games.