I've emailed this to Natalie, but someone else might possibly find i useful, too.
I can help a little bit.
I'm interested somewhat in the name as one of my grandmother's sisters married one.
I found this listing in the SSI info: PENDERGRAFT, IRA 443-01-9116 OK 6 Aug 1904 Jul 1985 OK Tulsa, Oklahoma 74105 Tulsa, Oklahoma 74105 Soc. Sec Index
Ira Pendergraft Age: 25 Estimated birth year: abt 1905 Birthplace: Oklahoma Relation to head-of-house: Head Spouse's Name: Mattie Pendergraft Race: Indian Home in 1930: Dawson, Tulsa, Oklahoma>>
If this is the husband of my great-aunt, her given name is wrong (she was called Minnie, not Mattie). However, they were divorced sometime along about era, so it could well be her husband. I actually think they were divorced before 1930, as here's what I found for a 1930 census listing:
They had a son Oswald. I met him once, back in 1946 when I accompanied my grandmother on a trip to California to see this sister and another.
Ira and Oswald are listed in the Dawes Roll (an important listing of Cherokees which was made over a period from 1894 to 1914; it was a basis for alloting lands to members of the tribe). 44874b 158PendergraftIra R. 44875b 4336PendergraftOswald