Concerning the 25th Wis flag. Since I could not find anything on it, I would say, having studied and made the colors of that era, take a look at the flags for the Wisconsin regiments listed on the Madison website and choose, especially the later ones. It should not be that difficult. Most Wisconsin National flags were made in Chicago and had a square star pattern. It should not be that difficult to decide on one. The size, by regulations is 6 foot by 6.5 foot on the fly, which when I measured a few originals in Madison is quite accurate.