My advise on the ChiCom SKS's is look at them closely. Look at the bore. Does the rifling look sharp? Look at the muzzle, does the crown look dinged?
Then wiggle the lever below the front sight and carefully (otherwise the spring and piston will fly across the room) take off the from gas return tube. Does the port in the barrel look clean and sharp or has it be gouged out? Do both the pistons look like they are in good shape or have they been pitted due to improper cleaning and corrosive ammo?
Is the dust cover on tightly or can you giggle it a bit?
When you are all done and decide on your SKS, take it home and clean the hell out of it. Polish the chamber to get it nice and clean. Make sure that the bolt/firing pin are really clean and lightly oiled. BE VERY CAREFUL in taking apart the firing pin as if you put it together wrongly, you can get a slam fire fully auto situation. Likewise, you need to clean it well of all storage cosmoline to make sure it doesn't every want to go slam fire on you. The first cleaning is really critical but there are lots of articles on how to do this and the reference to Surplusrifle has a good how to take apart discuss on the SKS.
I really won't put much trust in the SKS safety. They are so rugged and reliable, there is little except abuse and neglect that can go wrong with them . If you are buying a "new" surplus SKS it should be in a new safe condition, with the exception of needing a real good cleaning. If you are buying a "used" surplus SKS at a gun shop or pawn shop, then you need to make sure the guy who had it before cleaned it properly after any use of corrosive military surplus ammo.
I would buy one of the "buffers" for that are sold for the SKS and if it has been used, maybe a Wolf spring kit. Both can be purchased off the internet. Outside of that, you are probably fine. When you get it you will also want to buy a front sight adjustment tool and a better cleaning kit.
