Found: BBC show about a pair of metal detecting chums called "Detectorists"

Some BBC shows are hard to find on streaming channels (unless you subscribe to a paid channel like Britbox or Acorn), but I felt lucky to discover Detectorists on Amazon Prime (also with ads on freevee).

This charming show with Mackenzie Crook (Pirates of the Caribbean) and Toby Jones (The Hunger Games) follows the quiet life of a pair of metal detecting chums as they search the British countryside for Roman treasures and instead find true companionship. I enjoyed their hilarious sad-sackery and the competitive intrigue among fellow detectorists. Viewers who continue to the end of the third series will find a nice treasure.