Most of the "sniper" rifles you see for sale are just that, non-PU sniper models converted with a modern replica scope, and they sell for $800, so I'd say it wouldn't hurt as long as you don't use a rare marked gun and you or your smith mount the scope to the original specs.
"Call on God, But Row Away From the Rocks" -Hunter S. Thompson
“Freedom is something that dies unless it's used” -HST
"In a nation ruled by swine, all pigs are upwardly mobile—and the rest of us are F###ed until we can put our acts together: not necessarily to win, but mainly to keep from losing completely. We owe that to ourselves and our crippled self-image as something better than a nation of panicked sheep."-HST