Does the Serial Number located on the small 'flat' underneath the Barrel, close to the Frame...does it match the Serial Number found on the Butt?
And, also, can you post some close ups of the in-set Rear Sight assembly?
Some Revolvers were sometimes ordered to have a Target type Rear sight, while having a plain Service type Barrel/Front Sight.
Sometimes, someone had a Gunsmith fit a Target Type Rear sight, to a service Revolver, and, the Sight so fitted may or may not have been contemporary with, or of the same kind, as the Revolver would have had, were it a factory Target Model.
So, at a glance, it is hard to say which may apply to the Revolver you have.
More images, close ups of the Rear Sight as seen from above and the rear and the sides, and, a look to the respective Serial Number locations, may aid in determinging what it is.
Very pretty! Regardless! Love those early 'dish top' Square Butt Stocks too.