As far as I know, the Palmer Model C from the second catalog seems to be one of the most rare. Everyone buying Palmers in that era wanted the plexiglas window style. Even Ks, Ls, and the Supreme M seem to be around aplenty. But the Model C, I've only seen about 3 or 4 pictures of them. Here's a very good example of Gene Balner's tribute to the Rambo. Enjoy!