A member of Ohioans For Concealed Carry has a thread going about spent brass for sale that started out at 800 pieces and is currently at 1600.
Frankly I don't know if $6/100 plus shipping is a good deal or not.
Here's the first post time stamped Mon Jul 10, 2017 5:07 pm:
Here's the latest post:800 PMC once-fired .223 casings, not range pickups, straight from the brass catcher. $6./100 FTF around Solon, Ohio, or can ship at flat postal rate.
http://ohioccwforums.org/viewtopic.php?f=32&t=90130Thu Aug 10, 2017 7:50 pm
1600.