Depending on your unit's (your) commitment to authenticity, the next step would be to "campaign" your current impression, not that I'm advising it:
- If you haven't already, install natural gut strings and a genuine skin head on your Gardner (instead of the standard Nylgut strings and imitation skin plastic head that comes with the baseline Gardner). This step comes with the caveat that natural strings and head require frequent adjusting in the campfire setting, as the evening dew falls, if your pards and you have the patience for it (cigars and whiskey help with that).
- replace the Eagle brackets (ouch!) if that's what your Gardner has on it, with simple brackets. Eagle brackets were not yet very likely on an Antebellum to CW-era factory banjo (not to say that none of them ended up that way).
-Beyond those less-than $100-combined steps you can quickly move into $800-$4000 territory for a museum/collector grade reproduction or restored banjo.
None of that was worth it to me in my reenacting impression, which remains at the "10 foot" standard. What's good enough for me is that my 'reproduction' Bell banjo is authentic enough as a talking point. I can verbally expand on the particulars of an authentic instrument for the occasional over-focused on-field maven or really detail-fascinated spectator.