So from the BP section of the 1975 Guns Illustrated I found three turn barrel rifles.
Esopus TB-1 percussion .45 cal two barrels on swivel, single, each barrel has its own sights lock $139.95
Hopkins and Allen Turnbarrel o/u percussion 45 cal two barrels on swivel, single, each barrel has its own sights lock $139.95
These do not appear to be the same rifle but close in lay out, different lock plate and cap box in stocks , different trigger guards, and Esopus has sort of a fore stock.
Dixie Flint Swivel Breech Rifle .45 On this the barrels each have their own pan and frizzen in addition to sights and the barrels are "Paneled" like the Esopus to provide a scant fore stock. Very nice stock in the add with embellished rectangular patch box.....a mere $450 in 1975 (ow! buddy's Mauser action , scoped BSA cost only about $200 that year)
Also available as a percussion gun at an amazing savings at only $325 in 1975.....about what a PFC took home a month in 1975.
I will say that Tim Murphy would likely have been happy with the looks of the Dixie rifle in his tree at Saratoga.
I have yet to find the model flinter I still seem to recall was offered by Century though it looked much like the H&A percussion gun and I suspect was made by the same folks.
I believe it appeared in their "Restore your tired old rolling block" adds for years.
I can not recall ever having handled any of these swivel breech or turn barrel guns though they always fascinated me since reading of Murphy as a "ute"
-kBob