There were a number of sanitary fairs up north in bigger cities and many displayed captured Confederate flags. The Cincinnati fair displayed some of the flags taken at Missionary Ridge that were on their way from Grant's army to the War Department. The same fair also displayed two flags taken at Vicksburg (one LA, one Texas) from Gen. Frank Blair.

Several of these fairs published catalogs like this one but most you have to find details in local newspapers.

Greg Biggs