Here's an obit on his son which mentions his mother, Jasper's wife, her name and city of residence at the time of this obit. She may be the heir to that dog tag. Great find and good luck in your continued search.
Ronald Letterman,Sr.
Ronald Eugene Letterman Sr., passed away July 11, 2003 at 3 a.m. at Freeman Hospital, Joplin, Mo.
Ron was born June 13, 1946 at Ava, Mo. He was preceded in death by his father, Jasper Avery Letterman; and one son, Van Kenneth Letterman Henson.
He is survived by his mother, Ada Nalley-Benson, Springfield, Mo.; one brother, LeRoy Letterman, Gray, Ga.; two sisters, Mary Letterman-Hamrich, Griffin, Ga., Janice Letterman-Smith, Springfield, Mo.; two children, Ronald Eugene Letterman Jr., Joplin, Ronna L. Letterman, Joplin; dearest friend, Claudia Maxwell and Dolly and Chris Ramm and family.
Don.....