have a read here http://www.environ.ie/en/Legislation/DevelopmentandHousing/BuildingStandards/FileDownLoad,26938,en.pdf (new draft stairs regs)
you will probably need to get a local carpenter in to help, make sure he is building to http://www.environ.ie/en/Publications/DevelopmentandHousing/BuildingStandards/FileDownLoad,1651,en.pdf (the current stair regulations), if you search under spiral stairs on goggle you'll see several Irish sites but their generally more expensive than a timber option, a local metal worker may be able to help but again these prices in my experience are more than a timber stairs. best of luck