Have you found the information you are looking for yet? If not, maybe I can offer a new search to try. I see from Azor's profile that you previously searched for records in FamilySearch. Have you considered searching the family trees there? It appears that Lewis Shearer may have an older brother Uriah. There are no sources listed for the statement that he was born in New York in 1770, but searching for records on this collateral relative may help you find what you are looking for.
Good luck with your research!
