I have a number of SKS rifls or various origins and vintages. The only one I have moded is my $99 Chinese I bought from Century Arms. I took off the bayonet and ground off the bayo bracket. I have drilled and tapped two holes in the side of the receiver to take the base for a target peep sight. The target sight is worth more than the rifle, so not a reccommended option. I happen to have lots of sights from my shooting days. But I think the flat-sided Williams Fool Proof sight as used on a Winchester 94 would probably work. Used ones are cheap at the gun show.
The first time I used it in a vintage rifle match I won most of the matches and the aggregate by a fair margin. I am 65, so the short sight radius is not that good for my eyes. A scope would be better.
I have the solid steel receiver covers on two other rifles (a Russian and a Yugo). One has a red dot, the other a 4x scope.
For a proper test, I should put a 20X scope on each of them, and bench shoot off sandbags.
I am shooting milsurp, not Russion commercial. It shoots very well. My sense is that the Norinco shoots as well as the other rifles, maybe better.
One of these days I will put a 20X on my AR15 and on an SKS and shoot them for groups. I know the AR shoots under 2" with military and about 1" with match ammo. (HBAR) I doubt the SKS is that good, but it shoots well enough that I have no hesitation in shooting it in a vintage rifle amtch against #4's, etc.
I am 6 foot tall. The Norinco has a stock better suited to my wife. If you are tall, a YUGo is better, or the synthetic stock.
FWIW, my son converted a Norinco to synthetic stock. Functionality went south. he also converted it to a detachable 30 round. That too was a disaster. Put it back to the original stock and mag and its is perfect.