I have the name Man(n) in my tree. They were from Bromfield Cumberland and Holme Cultram Cumberland. The earliest I have is a John Man(n) b1666, his son Joseph Man(n) born 1689, his son John Man(n) b1718 who married Mary Temple. Their son Mungo Man(n) born 1749 also had a son John born 1784. I dont have the details of Mungos siblings. Just a suggestion to try Cumberland area where name was quite prevalent around the time you are looking for.
Sandra