All SKS are C&R, period, except for the assorted Norinco and even they, because of their age, are now C&R. For some reason the SKS were specially called out as "curios" by the ATF long ago even though they were much younger than 50. Why did the ATF do that? Don't rightly know. It's a mystery because usually a "curio" qualifies because it's very limited production (SKS is huge production) and/or an obscure caliber (SKS, not!). But I don't argue. The Norinco/Chinese made rifles were specially excluded initially but, as I mentioned, some are now 50 and automatically qualify as "relics" that way.
Rome
PS Just thought I'd throw this in here: Believe it or not, this is a Yugo 59/66 SKS. Nothing was modified but a new bullpup type of stock was installed around the action. Chk out SGWorks.
I can have it back to original configuration in about 10 minutes so no harm, no foul. The SKS is really a rifle of the ages.
R