How cool would it be to have The Bedford Flag as a mod or added to an existing flag mod? It was supposedly carried by the Bedford Minutemen to the Battle of Concord at the Old North Bridge on April 19, 1775. Latin on the flag says "Vince Aut Morire", meaning "Conquer or Die"!
Tie it into the Bedford Station location in some way? Maybe have a tattered version of it flying somewhere nearby? Having it be the objective of a Preston quest mod makes sense, too. He would know it was preserved by sealing it away in a climate-controlled vault before the Great War!