Send a message to the person who requested a photo of the grave monument of Martha Austen with the following comment:
I think this is one of my ancestors. My family tree shows a Henry Austen burried 12th December 1713 at East Grinstead. He was married to a Martha. The only discrepancy is that my records say he was baptised July 1764 which does not fit your researched birth year of 1767.