Hi Tony. One of the reasons Gerry's superb layout works so well is the availability of quality N gauge RTR BR Outline locos and rolling stock. There are no RTR Irish locos or rolling stock for N gauge, so it would need resprays of British outline N gauge models, or if diesel era possibly 3D bodies to put on modified BR chassis, or adapted N gauge kits. If you are going for steam era than it will be easier for you to convert British outline RTR stock. For modern era there are suppliers of vinyl body transfers as an alternative to repainting. Noel