NYPL has an extensive digital collection, and I came across a Mugnier stereo of the Lee Monument:
Now, what’s particularly cool about the NYPL site is they have a utility called the “Stereogranimator” that simulates the 3D effect you’d get looking at one of these cards with a 3D viewer. It’s kind of neat:
GIF made with the NYPL Labs Stereogranimator
This is quite interesting, and I’ll see what else they have in their collections.