Harvesting images from a Public Domain internet or social media site is a delicate issue.
That's why I'm trying to do the right thing here.

If I can't get permissions for the images, I guess I could delete them from the document and just say; "There are known guns with these patterns in the damascus barrels."
I also need to get in touch with Christian Schnura, the developer of the Thor II© application. If Christian says no, all of my work on this document will be for naught.
Thanks again for all help provided!