James Julia Auction sold one a few years back, it is white with black lettering. Both, the Heritage and the Julia auction are banners that were displayed on a wall, most likely outside in front of the building. The National Archives has several pictures and illustrations of U.S. Sanitary Commission banners in front of buildings. Also period newspapers have articles on sanitary fairs used to raise money to aid in the comfort of wounded soldiers. Each of the States had Sanitary Commissions that did the same thing for their State Troops, in the field and once the soldiers returned home.

Happy Trails!
Tom Martin