O12//UO23, 1873-9 Official Cover Collection, 17 different covers + 9 Post Office "Specimen"in original box,entires, includes: O1 (2), O17, O37, O49, O72-73 (one cover), O74, O98, O99, O114, UO2, UO6, UO23, many with printed imprints, several with interesting aux. markings, generally Fine or better, impressive group. (see online scans). (Image)

CV. 1,500-2,000