Could be, but only a search of factory records and a factory letter will tell for sure.
I would guess the grip frame would have an N stamped on the lower left hand corner if the factory did the work before shipping.
Bill
I have a 19-2 nickel frame, blue cylinder and barrel, it lettered. To know for sure get it lettered. I never read factory literature describing it a "pinto" they were called a two tone. I just looked up my letter from Roy Jinks and it was "special combination two tone finish of blue and nickel." Larry