Hi moneymoneyp - I don't think there is any 7-year rule re stamp duty and it appears you would not be considered a First Time Buyer as regards stamp duty as you have previously owned a house. However you would not have to pay stamp duty on a new house/apartment under the 125sq.m. floor area if buying as owner-occupier, and for new houses with floor area in excess of 125 sq.m. there is relief that would leave either no stamp duty or very little payable unless house very expensive - again of course if you are buying as owner-occupier.
If buying second hand house then no duty if not in excess of €127,000, over that amount then first €125,000 would be exempt and amount in excess of this up to €1,000,000 charged at 7%, and balance in excess of €1,000,000 charged at 9%