I know that this thread is a little "stale," but I do have something to add to it--so far not mentioned by anyone else--so here goes.
1. I'm in Canada and I spoke to the Abbot of Birken Forest Monastery in Kamloops: Ajahn Sona, Thai Forest Tradtion. He informed me that as this monastery, the "cut-off age is 45." He was quick to add that it 'has to do with demographics." He didn't elablorate and I didn't puruse it, but I surmise it has to do with Dana. There's not a lot of lay support yet in Canada to support many monks, so perhaps he's concerned to see that support go to candidates with . . . more potential? I don't know. Anyway he suggested that if I wanted to go forth I should go to IMF in Thailand.
2. I once heard Ajahn Jayasaro speaking to a friend of mine who is perhaps 63 ish, and asking him if he hadn't thought of ordaining. My friend said that he thought we was too old. The Ajahn smiled and said: "you seem reasonably healthy..," and he more or less encouraged him to consider it, and put forth both Thailand and Sri Lanka as possibilities.
3. One monastic in the UK I was communicating with by email echoed that 45 is the age in the West.
So, there is a cut-off age in at least one Canadian monastery. That seems to be a broader limitation across much or all of the West. There is no cut-off age in Thailand or Sri Lanka.
The question I wonder at is: ok, so ordination at 53 (my age) in parts of Asia is a possibility--it's not excluded by rules or convention. But how "realistic" is it setting forth at my age? I'm seriously considering it since my family is mature and can spare me now, and since materially there would be no hardship. As it stands, I'm a teacher in a technical school with a pretty sweet opportunity for intensive summer practice during the 9 weeks annual vacation, then there's time off at Christmas, time off at spring break. The work isn't too demanding since I teach more or less the same courses each year, and it leaves enough time and energy for several hours of sitting each day. Yet the idea of going forth really, really appeals to me, and if the Buddha hadn't thought it was of value he wouldn't have recommended it. At the same time my present circumstances are pretty good, and I could move ahead as an 8 precept upasika with fairly generous--for lay life--opportunities for daily and extended practice. If I were 23, the answer would be clear, and I'd definitely go to Sri Lanka. But at 53, one is already grappling with decline to some degree, and materially there's no recovery time left if one goes forth and it's not what one thought it would be.
Aya Khema ordained at 54. But she returned to the West eventually. It seems that most do, doesn't it? Does anyone know of others who have ordained so late in life?
Friends, have you any thoughts? concerns? heckles? . . . moans?