If I recall correctly, I paid $35 for the 1000 "once fired" Winchester brass cases I'm using now. Plus shipping, which was about $7. These are tumble-cleaned but otherwise not processed. That's pretty cheap, but the seller has a deal with several police ranges and indoor ranges, and he does volume business with low overhead.
I've bought "once fired" cases that appeared to have been fired a lot more than once.
Clues included split case mouths, thirty-year-old head stamps, etc. If your cases are really fired only once, I think reloaders would be willing to pay a premium for them.
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If God didn't want us to own guns, why did He make the 1911?