I got this from Historic Images:
http://www.historicimages.com/
EDIT: they also sell on ebay.
As their web site explains, they are involved in digitizing newspaper photo archives, which they then sell piecemeal on their site.
There are other similar outfits that I search from time to time, some of which are multiple sites owned by one organization.
Examples:
MMGarchives.com
NewspaperPhotographs.com
JP-TheMint.com
If you get on the email lists, you will find for some of them that they send you links to new sites that they name similarly, but which have content from different times or sources, or may offer images in different price ranges.
I did not see any other photos in this series, but I suggest going to these sites and any others you find and trying more search terms, because you never know what terms the person who wrote the listing will use - it can depend on any terms that happen to appear on the back of the photo as well as the listing writer's thoughts.