I do not live near the Bethel-Greenwood Cemetery, but perhaps these sites can be helpful as you prepare for a visit.
The first link is to the Bethel-Greenwood Cemetery. There is a photo of the gate. The names you are looking for are listed.http://www.okcemeteries.net/lincoln/bethel/bethel.htm
The 2nd one is to the findagrave site. There are no photos of the tombstones that you want, but by searching for a cemetery, Bethel, in Oklahoma, you will get a link to the one in Lincoln County. There is a map, sort of, which shows it is near Kendrick.www.findagrave.com
This last link is to the Lincoln County Museum in Chandler which has a genealogy area. You should be able to find a schedule for when it is open. You might find some helps there that would be worth your time.http://www.rootsweb.ancestry.com/~oklincol/museum.html
I hope you find you visit a successful one.
Mary in Oklahoma