Here in Scotland the universal tartans seem to be the red Stuart, dress Gordon, MacKenzie and one or two others, mainly because these are the ones the hire shops offer. There are lots of district and national tartans which are suitable if you don't feel you have an affinity to any particular clan. If you want a particular tartan then the kiltmakers will know where to get it for you (just pick a good kiltmaker, plenty of them here) and if it is an unusual one the weaver may have to do a special run for you (at an extra cost) so it is better to stick to a mainstream tartan which is always available.