Seem to be a few more UNloaded around.... and you can mail the unloaded ones. They are scarce enough that I think serious collectors would NOT balk at $15 (or so) apiece.
Seriously, there ARE cartridges out there which sell for a lot more: .256 Frazier/.26 Swift runs about $200 a pop IF you can find one for sale, .28 Ross (the experimental which led up to the .280) is rare enough that they go by auction only.
These ones aren't in THAT category of scarcity, but they sure ain't common, either.
You have yourself a little treasure there. Good!
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