From the products of John Dundon's remarkably extensive research in Ireland, I can only find one likely candidate.
There was a Michael Dundon baptised on 16 September 1832 in Bruff, County Limerick, son of Phillip Dundon and Mary O'Shea. There are 5 brothers and sisters, too.
Have you looked for Michael and Catherine in the 1880 census? This may give more credence to a birth date a litle later than 1825. I can do you a look up if you want. Calculated birth years are often inaccurate. There was no reason for people to care what their age was exactly, because no-one was going to get a pension!