You may be in luck because nearly 200,000 images from the New York Public Library are now online and available for free use.
“The New York Public Library just released a treasure trove of digitized public domain images, featuring epic poetry from the 11th century to photographs of used car lots in Columbus, Ohio from the 1930s. Over 180,000 manuscripts, maps, photographs, sheet music, lithographs, postcards, and other images were released online Wednesday in incredibly high resolution, and are available to download…and images can be sorted by century, color, genre, or library collection.” – Andrew J . Hawkins, The Verge http://www.theverge.com/2016/1/6/10723680/nyc-library-public-domain-images-digital
View the public domain image collection here: https://www.nypl.org/blog/2016/01/05/share-public-domain-collections