Not sure this is your James, I have been looking in Ontario region based on daughter Annie having lived there - you may have his death in NS, I did not check that...this death of this James is in New York.
Name Petroff, James
Burial location Sec. S, vet. plot, grave 1250
Born Sept. 20, 1894
Unit Co. M, 108 Infantry; WWI
Died May 26, 1966 aged 71
Type of tombstone U.S. marker http://mcnygenealogy.com/cem/vets-riverside-s4.htm