I pulled these from the AK forum and brightened them up with some contrast so you can see the details:

1970 Tula (Apparently the last AKM with bottom sling swivel location on the stock)

1972 Tula (source says 1971 Tula parts were sent to Egypt for the Maadi AKMs)

1973 Tula

1975 Izhmash AKM

1976 Tula AKM

1977 Tula AKM

The reason for the predominance of Chinese Type 56 rifles in Afghanistan is mainly because of the Agency's efforts in the mid-1980s to funnel boat loads of them into Pakistan for the training and logistics camps, along with the Pakistani ISI.

There was a former SF E-7 who had gone the O route, then went to the Agency, who helped mastermind the small arms mix scheme, along with the UW training program for the Muj.  It was part of a major series of policy changes from the Agency's previous posture of barely giving minimal support to the Muj to just harass the Soviet effort without any discernible hand from the US.  That was in the days of .303 Enfields from old British inventory, where British MI6 had found a way to pawn off old war stock that was no longer really viable in the 1980s.

When the new Central Asian station chief came in, he wanted blood, and had the ear of a particular Congressman who also wanted to ratchet up the UW effort against the Soviets.  These guys listened to the advice of the SF folks, and built a logistics feed that was backed with Saudi money, matching US and other Islamic nation donations dollar-for-dollar.  They went around shopping for weapons, and got the Chinese Type 56 rifles along with that effort.

I have a book on Afghanistan in Russian that is really cool, meant specifically for Spetsnaz GRU veterans of that conflict, showing all the different types of small arms they encountered.  There are several pics in it of captured weapons caches that the GRU Spetsnaz interdicted, as that was their primary operational profile, focusing on intercepting shipments coming in through the mountains along the Afghan-Paki border.  Most of the AKs are ChiCom Type 56s with the under-folder spike bayonets.

looks like Robs pictures.
if you go to lulu.com he has 12 volumes of picture books w/ great color photos.
search "rob stott"

I pulled them from another forum and brightened them up.