I looked in the 1910 Posey Co, IN Census and found your John Bunch and Sarah R.
Bunch John 39 married twice. married 9 yrs.KY KY KY Sarah R. 56 married twice. 6 children 3 living IN IN IN Felker William 28stepson widowed IN IN IN Bunch Carl 12 son IN KY IN
Living with Fred Curley he was a servant Bunch John Dec 1878 S KY KY KY
There is a Sarah Felker in 1900 Vanderburgh her birthdate is April 1860 IN IN IN and she is widowed, but the age does not match the 1910 Census.
In the 1880 Census I did find a John P. Bunch. John P. BUNCH Age:1 Estimated birth year:<1879> Birthplace:Kentucky Relation:Son Home in 1880:Glasgow Junction, Barren, Kentucky Occupation: Marital status:Single Race:White Gender:Male Head of household:Greenberry BUNCH Father's birthplace:KY Mother's birthplace:KY
If I had a little bit more info I mite be able to help.These are possibles though.