I have two Irish SIM cards for cell phones. I'll loan them out if you promise to return them upon completion of your trip and put on enough credit to cover your use. You benefit by knowing your Irish number before you go and I benefit by extending the life of my cards. Cards expire after a time if not recharged. Since it is not likely I would ever be returning to Ireland, the only use to me is that I can then loan them to someone else. I have one TECSO card and one O2 card both with Irish numbers.
PM me if you are interested.
I'm sending it to someone who PMed me for it and who will return it before the end of May so it has to be after that.