Thanks for writing back.
There are 102 burials listed in Sanderson per the cemetery records of Ray County per Genealogytrails.com. There are 148 per Findagrave.
I was hoping to contact the McKinney heirs (former owners both now deceased) in hopes that there is somewhere an OLD ledger containing the names of all buried there.
The cemetery is now completely fenced, according to the last information that I had, and goats free-roam the cemetery.
Perhaps you could pursue contacting the McKinney heirs on behalf of the museum.
That's about the only available option at this point, it seems.
Robert in Arkansas