The dark wood pistol handle that Matt Dillon notches in memory of his friend is replaced in the very next episode, "Young Man With a Gun," by a pistol with a white bone handle. The difference is easily noticed. Given the poignancy of the end of this episode, the immediate change of pistols is peculiar.
This storyline reflects an actual event that happened when Wild Bill Hickok accidentally shot his deputy Mike Williams.
This story starts with Chester having sprained "both" ankles. This would imply that Chester's famous limp was not due to a wooden leg.
Matt carves a notch in a dark wood grip on his pistol, but this grip was not a special grip just for this episode, but a reversion to the wooden grips seen on his pistol in most of Season 1. His pistol already had light colored faux stag grips (they were plastic, not bone) for at least eight episodes before this one, and after this episode he went back to the faux stag grips.