I think I would search a little harder for some heavier fabric. Remember, for your reenactment purposes it does not have to be a named tartan pattern. When I did reenactment, I was able to shop the local fabric stores and get 100% wool or wool blends in some serviceable weights for just a few dollars a yard. This time of year is a great time to look for woolens on the discount tables, as fabric stores clear out their inventory of cold weather fabric making room for lighter summer weights.