According to his profile page, he died in Watertown, MA.
With that information, I did some googling and found that one John Stratton is buried there, at the Old Burial Ground there (might now be part of Billerica. Someone has transcribed the gravestones here.
His gravestone reads:
Here Lyes ye Body of Mr. John STRATTON; Who Deceaƒed Februa'ry the 20th 1715/6, in ye 57th Year of His Age
So that's not the right man (perhaps a son?)
While there are 1691 burials there, there is no stone for him, so IF he is buried there, he either didn't have a stone, or it was buried/lost.