Open the OP's photo and then click in the area of the engraving - it says "Presented to high law enforcement officer, 1959,
national trophy individual pistol match."
The correct serial number should be in the ejector rod channel under the barrel, on the rear face of the cylinder, and on the bottom of the grip frame. Its also in two other places more difficult to read.
Looking at the engraving, it appears that the engraver may have worked over the S&W logo in order to create a badge or shield with 1959 in the middle of it. Just a theory, and maybe not a good one.