The feilidh-mhor, or great kilt, was only worn from the the end of the 16th C. until the beginning of the 19th. C. So if you're looking for 1115 AD, you're out of luck as far as the great kilt is concerned. Stay tuned for more history to come...Let me check out a few sources and I'll post again as to what might be more period correct. My experience with LARP events have been that historical authenticity is not of the upmost importance, but if you want to look period, then guid on ye for the effort!