If you really want to glass an SKS, consider the forward scout mounts that replace the rear sight, you just tap out the pin that the rear sight is attached with, and mount in a small rail that allows you to mount a LER scope (Long Eye Relief) a.k.a. a pistol scope, or you can go un-magnified with a 1x red dot or holosight on the forward mount.
The forward mount is the cheapest best alternative for mounting glass besides going with an AK mount to the left side of the rifle and having to permanently alter the rifle.
The upper receiver mounts are considered less than ideal due to the extreme stresses exerted upon any optics mounted on one of these adapters.
If you are familiar with the method of semi-auto operation on the SKS, you will know that the upper receiver cover is not a solid foundation to mount an optic onto. You will find that you will lose the zero of the optic after about the 15th shot, and you will then chase the POA versus the POI all over the paper, getting frustrated and burning ammo for nothing.
Save your money, don't get an upper receiver cover mount. Go with a scout mount or think about what you are trying to do. The SKS (without heavy and intensive modification: read more than the value of the rifle) is not a sub or even 1 MOA rifle at 100 yards due to many factors including sub-par ammo selection, short sight radius, heavy triggers, etc.
I believe that you will eventually find that at least 90% of the after market crap for the SKS is just crap, and most folks eventually come back to its original configuration after dumping 2x's the amount that they paid into the rifle to tacticool it up into something that its not.
