UNICORN! Russian Imperial Berdan II Infantry Rifle Birmingham Small Arms

Absolutely impossible to find (in many years of collecting I saw only one for sale). Russian Imperial Berdan II Infantry Rifle produced by Birmingham Small Arms Factory (BSA) in England. After Berdan I by Colt Russian Imperial Army contracted BSA to produce about 30,000 rifles before production of russian made Berdan II started in Tula, Sestroretsk and Izhevsk later on. This particular rifle was brought here by US marine from Afghanistan a few years ago. Original hardwood stock with cartouche (Russian Imperial Eagle, PK and 1870 date) still visible, buttplate is unserialised so is the bolt with small cocking knob (all correct for BSA rifles comparison between BSA and other Berdan II bolts).
Russian barrel address and other markings are clearly visible, there are no import markings. Function is fine