Spottig a fake/replica, restored, or correct refurbed PU is no longer simple. jjjxlr8's post is helpful though.
The safest way right now is to get one of the Molot stamped rifles with IO import markings currently available from Classic arms or one from Rguns. These are well vetted and were PU snipers when they left the factory in 42-44 with varing degress of refurb. The Molot stamped PUs with IO import marks are not recently made my Molot, nor recently redone by Molot.