I saw one of those for sale a while back, but didn't buy it. Joseph Vorisek shows that model in his book on Hopkins and Allen, but there is only a picture and the comment that he has been unable to find much about it except that it was probably made from c. 1893 to c. 1898.
It appears to be a straightforward design, though, and should be easy to disassemble, though I recommend against doing so unless there is a need. If necessary to disassemble, get cup end punches from Brownells so you don't mar the pins or batter the frame.
That revolver is an oddity in that it is a concealed hammer type with a solid frame, not a top break. The hammer is concealed the same as some IJs, by using a high side frame, then pinning in a top cover.
There is still a lot of info undiscovered about H&A, for all that they were a major arms manufacturer for nearly half a century (1868-1916).
I know of no source for parts, though some could be made and others probably adapted.
Jim
