The stamps were actually found on Pop Art Machine and I had loads of fun playing around the site so I had to share!
The gallery section has many options that you can search from and you can either order it through them or digital downloads are available starting at $2.99.
They remind me of these pieces of art from Natural Curiosities international stamp collection,which I spotted at the NYIGF.
You could even go into the studio and play around with the image and do this:
Have fun playing!
I must add this source to my Little Black Book of resources! Have you checked it out yet? I’m adding new sources everyday. Have any suggestions for additions? Email me at firstname.lastname@example.org.