Pancake lock "Corbin Cabinet Lock Co" - Rare?

[timof5stars]

I stumbled across the following pancake lock which I figured was likely very common, mainly because Corbin is so prolific
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This lock is in exceptional condition but I haven't been able to locate others like it. It did not come with a key - and none of my push keys open it. Still, in order to correctly price it, I need an idea what others like them have sold for. Do any of you have this in your collection and if so, do you remember what you paid for it?

Oh, one more thing. The back side of the lock has a very nice repeating circular pattern where it was polished out:
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