According to the Uberti website, their version of the Schofield is available in 45 Colt, 44-40, and 38 Special.
Their version of the Russian model is available in 45 Colt and 44 Russian.
They also mention the calibers their replicas are available in are true to the originals, which is baloney. The Schofield was only ever chambered for 45 Schofield, the cylinder was not long enough for either 45 Colt or 44-40. Same with the Russian model, its cylinder was not long enough for 45 Colt. Uberti Top Break: No. 3 New Model Russian, No. 3 2nd Model
The only replica of a S&W top break with an adjustable sight that I am aware of is the Beretta Laramie, which is a replica of the New Model Number Three. It has a rudimentary adjustable rear sight, I believe it is drift adjustable. I do not see the Laramie on the current Beretta web site, so I do not know if it is still in production. They sometimes show up on Gun Broker and similar sites.
There are a couple on Gun Broker right now. Guns - Online Gun Auction - Guns for Sale at GunBroker.com
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