Wow, a llot of info there some good some useless, you need to research! Read the sks stickies at top of this page, lots of knowledgeable people on here have done a lot of research on sks. Curtton being one of them! If you find an unissued, non refurb I will pay big dollars as they are like hens teeth. I have never seen one, they at least have gone through one of the refurb plants! There are acfewcrifles that would possibly be considered BBQ painted but most that they are alluding to are parkerized, I have seen about 3 different types not including the aforesaid BBQ, the parkerizing is non glare and similar to the stuff they use on our military rifles/shotguns/ hunting rifles these days! It doesn't really matter which you use unless you think the glare of a blued rifle would spook whatever you are hunting! Matching is nice, hard to find matching mag as the importer didn't specify that when they etched the import symbols on the rifle they were to put the same mag. Back on the rifle, they are around and if you are using it as a collector then it may matter.
Laminate stocks are supposed to be stronger, I like the look of most birch/standard stocks but have both! If you hold the barrel with one hand and the stock with the other, try to move it forward and backward, if it moves, ( pretty normal) it makes the rifle a bit less accurate, you can get YouTube videos on how to fix this, not a big deal! Cleancthe rifle when you get it, more YouTube videos on this too, most important is the bolt make sure it is cleaned very well and the firing pin rattles when shook back and forth. Some earlier rifles had spring loaded firing pins and you wouldn't hear the rattle but need cleaning too! Make sure the bore and chamber is cleaned well too before firing could be some Cosmo in there if it hasn't been cleaned before! I cannot confirm but many knowledgeable sks folk, say that the early non chromed bores are a bit more accurate than chromed but the bore doesn't last as long! The chrome lined are supposedly a bit less accurate, not sure why, but last a very long time, if cared for! Remember to completely disassemble the rifle and clean it very well, youvwill have a more enjoyable experience and learn about your surplus rifle!
Have fun!