This is totally my opinion and not based on (much) fact but here goes... If you read about the history of reenactments on Wiki (which is always right lol) you find that they happened early on by the Veterans of the war - then not much until turn of the Century and then not popular until the 1960's CW Centenial (I posted the Wiki info below if interested). Keep in mind we didn't celebrate the war afterwards like the Revolution when reenactments were common. Most Veterans were tired, cronically ill and many in the South were broke not to mention we were stunned by a Presidential assassignation and many of the promises made to the South (by Lincoln) were not even close to being honored... There was not much reason to reenact anything especially by someone in Alabama.
Not saying it didn't happen just saying it seems more likely that the gun was used in the war then repurposed for a reenactment… but I could be wrong. I just don’t think they were common.
From Wiki:
http://en.wikipedia.org/wiki/American_Civil_War_reenactmentReenacting the American Civil War began even before the real fighting had ended. Civil War veterans recreated battles as a way to remember their fallen comrades and to teach others what the war was all about. The Great Reunion of 1913, celebrating the 50th anniversary of the Battle of Gettysburg, was attended by more than 50,000 Union and Confederate veterans, and included reenactments of elements of the battle, including Pickett's Charge. Modern reenacting is thought to have begun during the 1961–1965 Civil War centennial commemorations. Reenacting grew in popularity during the 1980s and 1990s, due in large part to the success of the 125th Anniversary reenactment near the original Manassas battlefield, which was attended by more than 6,000 reenactors. That year, Time magazine estimated that there were more than 50,000 reenactors in the U.S.
In 1998, the 135th anniversary re-enactment of the Battle of Gettysburg took place near the original battlefield. There have been several estimates on the number of participants, but it is widely agreed that it was the largest re-enactment ever held anywhere in the world, with between 30,000 and 41,000 re-enactors participating. This event was watched by about 50,000 spectators.