I'm getting a freedom kilt in the near future and plan on wearing it while on a cruise for evening meals as well as thru the day.

My question is about a jacket to dress up the kilt for the evening. I have a tweed sport coat I only wear to funerals weddings and dog fights that I think might be possible to alter into a kilt jacket. Is this a reasonable alteration cost wise or would it be better to just buy a true kilt jacket?