Hi Lauri,
I appreciate you reaching out to me to offer your services. It means a lot to me.
As it turns out I reached out to the library to inquire. They offer a search for a very nominal fee. So I took it. The results for Philip Gentleman...it referenced the 1790 Census, that's all. I did review the census and there is no indication whatsoever that Philips estimate birth year was 1750.
1790 US Federal Census for New Hampshire:
Only one Gentleman is listed and that is Philip, from Senters Location, Grafton, New Hampshire. He is listed alone and over 16, which places his birth no later than 1774. I believe this is the Philip who married Jennie Palmer in 1791. Some might say that this is the Philip who was born in 1750, but that has yet to be proven. What is unfortunate is that there is no other listing for Philip born 1750 as he would still have family members in his household. As I looked at the census records from 1800 on I surmise that Philip was born ca 1771.
I did not check what census records may have been destroyed in New Hampshire for 1790. That could be a clue as to why Philip b ca 1750 is not listed.
Regards,
Eric Johnson