Higene,
As all the others have so carefully and expertly pointed out, it is an F. LLI. Pietta. They make a good quality, but not the high end models, of reproduction Itallian made BP guns. It is a good, serviceable gun, that with basic care and cleaning will last well beyond your own lifetime, just as the originals have. It is in excellant condition, looking as if it was valued by it's prior owner, and well cared for. I am not an expert on the value of reproduction guns, but, in my estimation it could fetch the same price as a new one costs today, which is somewhere between $250.00 - $325.00 or so. Not an excessively collectable or valuable gun, but certainly a nice one, that should be a fun gun to have an own.
Congratulations on your find, Very nice piece !!!
Sincerely,
ElvinWarrior... aka... David, "EW"
Here is one, all dandified up, that goes for around $325.00 new out of the box... (I want a pair of these myself, with custom made white patent leather flap over holsters... sort of a Wild Bill get-up!!)