The Library of Congress Geography and Map Reading Room has a couple of maps. From the site:
The Geography and Map Division (G&M) has custody of the largest and most comprehensive cartographic collection in the world with collections numbering over 5 million maps, 72,000 atlases, 6,000 reference works, over 500 globes and globe gores, and numerous plastic relief models, and a large number of cartographic materials in other formats, including electronic. The online Map Collections represents only a small fraction that have been converted to digital form. These images were created from maps and atlases and, in general, are restricted to items that are in public domain, meaning those which are not covered by copyright.