The coin is not authentic, and not expected to be authentic, either. It is either a re strike or just made for decoration purposes in lower fineness.
The way it`s mounted into the ring is very suspicious: under higher magnification one can see gray color of soft lead/tin solder.That cannot be accepted - Russian silversmiths made items of outstanding quality, particularly an objet de vertu this one pretends to be.
The box itself is no proof, whatsoever (newly made in huge quantities).
Where are the marks? Can you take a close up picture of them, please ?
All said, I think it`s not authentic. Let`s wait what other members of the forum have to say, but marks are needed, anyway.