I am looking for death dates, obituaries, cemetery information for the following couple:

John SHELTON, born July 1866, Tennessee or Kentucky, married about 1886, Texas, probably Wise County, to "Belle", and moved to McPherson, Stephens County, OK by 1930. I believe him to be the son of John SHELTON and Sarah HOWARD, born 1824, Tennessee.

"Belle" I believe to be Mary Isabelle PARKER, but no proof. She gives her birthdate as Dec 1866, and every census consistently gives her parents and her birthplace as Illinois. Her parents' names are unknown to me.

John and Belle SHELTON had 7 daughters, and one son, all born Texas:
Mary A., May 1886
Albert F., 19 Sept 1888
Cora E., 19 Oct 1891
Annie M., Oct 1894
Maggie L., Feb 1897
Florence Nanette, 23 Feb 1899, Wise Co., TX
Ida May, 1902
Nettie Mary Lynn, 8 June 1908, Bridgeport, Wise, TX

Some of their children die in Comanche, Stephens Co., OK - did they?
John and Belle are both alive, both age 63, in 1930 McPherson, Stephens County, Oklahoma federal census. When did they die? Where are buried?

Any help would be appreciated,
Laura