Has a serial number of 691867 and I don't think the grip is origional.
Side of the barrel says "COLT OFFICIAL POLICE .38"
and top of the barrel "COLT'S PT.F.A.MFG.CO HARTFORD.CT.USA." PAT'D.AUG.5.1884.JULY.4.1905.OCT.5.1926
Also there is a "53" stamped into the bottom of the butt under the grip.