Hey Olefin, if it's of any use, I think the images of the Shersen class boat from the links I posted are public domain.
I just checked the links to see if they were still valid and they are although the Google Translate link to the Russian model building site does seem to be screwy so you're better off using a direct link and translating it from there.
http://hobbyport.ru/ships/pr_206.htm
Edit: Posted the above before checking all the images and realised that the pictures of model kits are most likely not in the public domain. I believe all the "real-world" images are though because they're all twenty or more years old and/or from a nation that no longer exists.