Beginning with this episode, the freeze frames at the end of each act are drawings, not photographs.
In this episode, Robert Conrad (James T. West) carves a dollar sign into the saloon mirror with a suspected diamond. In the film "The Giant Spider Invasion", Robert Easton (Kestor) carves a dollar sign in his kitchen window with a suspected diamond. Both co-star Leslie Parrish.
While one can cut glass with a diamond, a jeweler would not advise it. While very very hard, diamond is also brittle; scratching glass with a diamond could easily chip the points and edges of the diamond. This helps explain why a record player's diamond needle eventually wears out, even though it's much harder than record vinyl.
The town sets look like they are the same ones from Gunsmoke. It's because they are. TV shows often used the same sets as other shows in order to save money. For example, Alias Smith and Jones reused sets from The Virginian in almost every episode. Bonanza's Virginia City was the same outdoor set used to make The Virginian movie.
West uses the knife in the toe of the boot trick popularized by Rosa Kleb in "From Russia With Love."