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Tough one Kevin. I'm having trouble determining the structures symmetry (if it has any at all), exacerbated by focus/resolution problems. If it is a hook then it is almost certainly incomplete (no prize there). Whoever collected/photographed it (?Mike Everhart) must recollect and look for further material, hopefully series of them, hopefully some of which will be more complete (and more revealing).
I know of one squid type only (extant squid) that has a single hook on an arm (two hooks in total on the intact animal; all other suckers carry conventional sucker rings) .... tiz a 'secret squid' .... All other squid that possess hooks, with which I am familiar, possess many of them, in two rows, either along the arms or arming the tentacle clubs (this is not to say the fossil 'cephalopod' shared the same body plan). Nevertheless, if this structure was a hook, or part of a hook, then more than likely there'll be many more of them locked in that matrix.
My guess is that those are teeth, rather than hooks, perhaps "baby teeth" from a ray-finned animal equipped with plate-like, crushing teeth. At first, I thought they might be dermal denticles (in part because of their small size), but most denticles I've seen have a flared ring around the base.
oceansofkansas.com has some photos of Ptychodus teeth, here:
You are correct, the webmaster of that site has changed the content of that page, it used to show a small "glob" of something that really didn't resemble anything, he thought it might be a squid hook. Those small teeth look alot more like hooks than the "glob" ever did! Sorry for the confusion.
The Peachnet.edu site notes that many of the fossils shown are "floor tiles" from Atlanta's Fernbank Museum. If those tiles are castings from the originals (seems likely: wouldn't want to tromp on the real thing), that could explain the mysterious reversal of the image Kevin provided.