When Barney's gun goes off in the courthouse, the outline of his one, and only, bullet is visible in his shirt pocket.
Sheldon Davis, aka Thomas A. Moody (Jay Novello), is escorted/forced to leave the neighboring county by the police in that county. The sign at the county line indicates he is being forced to leave (fictional) Pierce County, North Carolina.
This episode is featured in the background during the Mad Men (2007) episode entitled "Tea Leaves."