Tony,
There is a new number for AIS (listed in the notams). It's 061-703750 (from UK +353-61-703750).
FNG
National Flight Centre in Weston (Dublin) have a Super Cub I believe.
NFC
There are no a/c available for rent from Dublin Airport. (Other than clubs which require you to be a member, and still, they don't have tail draggers.)
Unfortunately I don't know much about the clubs on other fields. However you might be able to find out more at the forum on
Flying in Ireland
Hope that helps.
dp