This is probably a Bush model from 1941-1956 according to the information at the first link below. There are no known serial number records available for Peterborough. Page 27 of the 1950 Peterborough catalog at the second link below has more details.
Thanks for quick reply. This model is 18' by just over 36" wide or 37" with gunwales and has wood slat seats and 3 thwarts. I am currently working on it and will have photos once done.