This has become a good thread. The Traditions derringer seems like it is based off of the "Moore" "derringer that came out around 1861 to 1865. However it was a rim fire. The percussion aspect qualifies the Traditions derringer as "black Powder Curio/ Replica" like Arcticap noted.
Daniel Moore patented a single shot metallic cartridge
.38 Rimfire derringer in 1861. These pistols had barrels that pivoted sideways on the frame to allow access to the breech for reloading. Moore would manufacture them until 1865, when he sold out to
National Arms Company, which produced single shot
.41 Rimfire derringers until 1870, when it was acquired by
Colt's Patent Firearms Manufacturing Company.