Duke University announced at the end of last month a new digital archive from the Duke Special Collections Library. “Deena Stryker photographs, 1963-1964” is a collection of over 1,800 photos taken from 1963-1964, when Deena Stryker was in Cuba. They’re available at http://library.duke.edu/digitalcollections/stryker/.
You can do keyword searching or general browsing. A keyword search for Fidel found 272 results, including many “candid” pictures of Fidel Castro: speaking at a rally, looking for Cuban spaghetti, and, in one photo: “Fidel Castro showing Comandante Armando Acosta his cows.” Photo scans are good-sized and all the ones I looked at had very precise dates with some details like subject matter, province and city, people in the photograph, etc.
You can also browse through ALL the photographs if you really want to, or you can go through some of the subjects in the subject tree, which includes people, title (these seem to be particular events), person, province, city, or place.