commercial

Any information or comments on this gun are welcome. It's a pearl grip, nickel finish, .45 automatic, with a .22 slide. This was purchased recently in an auction along with a Berretta 9MM 92FS DA, and springfield-stevens .22 rifle, and a browning 12 gauge that were all owned by Sid Caesar...

Do engravers usually put their initials somewhere on their work? Where would it be? Also if not done by Colt, what could I assume this would add to the value of this 1955 commercial? It is lettered, but does not mention the engraving. It's also possible it may or may not have been refinished...