Pistol made by Hopkins and Allen @ turn of the century or before.
Richard 'Pistol' Allen died on 2002-06-30.
Richard 'Pistol' Allen was born on 1932-08-13.
Hopkins & Allen Company.
They made thousands of them.
£150
Try Cornell Publications.
about the the late 1800s
gun shows, custom ammo makers
Impossible to value with just the sn and no other descriptors
10-100 USD or more depending on specifics.
The cast of A Pistol-Point Proposal - 1919 includes: Alfred Allen Leo Lester Eddie Polo as Cyclone Smith Eileen Sedgwick
Impossible to answer without a detailed description of all markings, features, finish and caliber.