Welcome to the S&W Forums! Never heard of a Highway Patrolman Special. The Model 28 Highway Patrolman was basically a S&W Model 27, but without the nice finish and checkered top strap of the Model 27. Value definitely depends upon finish and the inclusion of original box, documents, and tools. An all-complete set and NIB, only factory test fired, in today's inflationary market, I'd say $1200-$1400 would be a good price, you might get more on the online auction sites or from a collector who really wants one.