Think it's already been covered, but it is a 1968 Jianshe arsenal SKS. The 26 inside of a triangle identifies it as a Jianshe arsenal, which is good, because those are the only Chinese SKSs that you can reliably date - all of the other ones have numbers and dates from all over the place. The fact that your serial number is a 12,xxx,xxx number means that is was made in 1968 because the Chinese numbered their SKSs by serial number equalling date, IE 1956 (original date the Jianshe factory started producing SKS) + 12 (from your serial number) = 1968. Had it been a 11, it would've been a 1967. You get the idea... A lot of this information can be found on Yooper John's SKS page. You might find additional information concerning your SKS there as well. Pricewise? Well, I think Classic was selling matching SKSs for ~$400 last week, but I haven't gone looking to be honest.