nice topic....
excuse my bias, but unique,"one-of-a-kinds" or relatively few, like t206 printers scraps/proofs/om browns, pre-production....
Leon, your Peck and Snyder might not be the one, but what about that rosetta stone you have?
no matter how many planks, wagners, how many triple stamped/ghosted / brown om out there??
only Leon
my 2 cents
Johnny