Steven, I just found this. From the 1901 census, there was a John Eaton at Matramane, Castlegregory, Killiney Parish.
He was 44 years old, married and a boat builder by trade. I don't have any details as I only copied the index. I rented the micro film from my local LDS library. Jeremiah King Co Kerry Past & Present has John listed (the only Eaton) and added the following: Symon Eaton was granted Ballenruddrie and Illanamin, in Clanmorris, 489 acres, rent L7.
Good luck & good hunting!