Thirtycal, you are a weath of information. I wish I knew half of what you forgot.
Eh don't give me so much credit - so much of AK knowledge is just 'good guesses' based on what we can see in photos. Alot of times what we think is true sometimes gets proven wrong when the 'right' photo is found. In fact, here's a great example: I have a fairly extensive collection of AK-103 and Saiga reference photos. I've been collecting them for about 5 years now. I decided to go back through the 2006 photos to look for examples of any CNC engraved serial numbers, which could lend authenticity to that crazy Saiga dude is selling. So the funny thing is that I just learned something right now that I never realized: The factory used two different serial number marking methods within nearly the same serial number range:
'
You can see in this photo that these rifles are only about 200 units apart, yet one is clearly 'stamped', and the other is clearly 'laser etched'. Also, the stamped font uses western style 1's, which I thought was fairly uncommon for modern rifles. Both of the Saigas in the photos are the 'dimpled+Y' variant, which was somewhat rare - only produced in '06, and never thereafter. The vast majority of Saiga photos I have (going back to '06) show laser etched serial numbers... Really makes me wonder why they would have two methods.
Anyway, I'm sticking by my claim that the seller's front trunnion has been re-engraved by some builder (either pro or home), since I've never seen any example of a Saiga with a CNC engraved SN. But as I've illustrated, it's possible I could be wrong . That's what makes researching AK's so fun.
-Thirtycal