I am based in the UK not the Republic of Ireland but my initial suggestions would be to look at three web suppliers:
They would be a good start point for getting supplies (at least by post!)
Ilford also operate a web shop.
Perhaps others may be able to chip-in with any "bricks & mortar" shops in Ireland.
This may be a longshot but the RPS (Royal Photographic Society) operate regional organisations, they may have one in Eire/Dublin - have a look on their website. I am sure they would welcome an email enquiry from you, even as a non-member. If they have an Eire region most will probably be digital shooters but even the region that I attend has people who have shot film etc and respect what/how I shoot. Worth a try.
Also, another forum site called Film and Darkroom User (FADU) may be worth looking at for Eire based contacts.
Enjoy your time there, a great city & do visit the Guinness brewery!