ATC private training?
Although Eurocontrol have very strict age restrictions, many other ANSPs do not. For example, I know people who started NATS college in their mid-late thirties.
As for self funding, I see so many threads on this forum from people who have done the same, and are finding it almost impossible to secure an OJT spot. If I was in your position I would send my CV, along with a cover letter explaining that I'm prepared to pay for my own course, to every airport I can find. They'll know if they have anyone planning to leave or retire in the next couple of years, and might be keen to save some money.
Good luck