Post Office Seals of the United States and Possessions
by Jim Kotanchik.
Probably THE 'go to' reference on United States and Possessions Post Office Seals. Covers seals from the 1872 Registry Seal through the end of the official government seals in 2004. 600+ full color images of seals, watermarks and related materials, published 2006, hardcover with dust jacket, 350 pages, 8½" X 11¼"
Retails for $85 - $135
$40 to your door (USPS Media Mail to US locations only)