There are some on eBay right now but the pictures aren't too good for making a comparison. You would actually expect them to be similar in appearance though. After all a 3/4 face bust of a particular person looks pretty much like another 3/4 face bust of that same person. After all for the early presidents that aren't that many contemporary portraits they can use for source images. After 1840 when photography started there are more potential sources, but even then the number is fairly small until the late 19th century. I belive Lincoln was one of the most photographed presidents in the 1840 to 1890 period and I think there are only something like 160 images of him.