The easy part is finding an appropriate Irish tartan pattern. Where it can get tough is finding someone that weaves it. There are loads of tartans that no one makes except on special order and that get real expensive. Black Watch is a good first tartan since it's such a common one and the dark colors look good on most anyone. I've found Black Watch fabric at Jo Anns and Hancock Fabrics on a regular basis, usually in cotton, but occasionally in a poly blend.