Firstly, welcome to the PU! You'll find lots of good info here, as well as a friendly bunch of "gun-nuts" (myself included) sharing ideas and opinions.
I'm not sure if you have seen the following website before, but check this place out:
(Click the "SKS" link on the left-hand side, and scroll down to get the links to the various webpages. LOTS OF PICS!)
I've used the information at this website to determine more information about my SKS rifles. My advice is to read through this site and see what you can find out.
Let us know how it goes.
PS: BTW, nice looking rifle! I think it is made in 1968 at the /26\ Jianshe Arsenal.
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