The Russian guns usually have a shellac coating on the stock, not the most durable finish at all. And if it is the dark reddish brown, shellac is not usually that color from the store. I had to refinish a hand guard and I ended up using some stain on it. Something for muzzleloaders with that reddish tint in it. Then shellac over that. The color of the handguard is now a pretty close match to the original but getting a perfect match would be a pain I would think. If it is gonna be a shooter, as someone messed up the barrel, perhaps just strip and sand it, and a walnut colored urethane or such would be more durable. They used cheap softish wood and a cheap finish when they rearsenaled those things. Otherwise someone else might have specific info on a good replica finish for rework or touchup.