Expect to pay in NI around £150 for a front tooth root canal and for a conventional crown from £300, this wil depend on complexity of treatment and type of crown you wish to go for, ie: all porcelain which looks the best or metal/porcelain. You may need a post which will put up the cost. Go to a dentist that offers you all the options not just a flat price, know what you are paying for. I recently had the same job carried out at 'bluapple' dental team in Belcoo, Fermanagh, excellent, efficient, modern, brand new practice. think they have a web site, worth a look.