Regarding North Korean army's standard "weapon of choice"-- more than likely, it's listed in a Jane's reference. Probably not a "burp-gun" or AK-47 variant, because the KORCOMs use human-wave tactics that require minimal individual fire. Perhaps a form of carbine, depending on what surplus China provides. On 'tother hand, pitchforks and trench-tools might do as well. When the Dear Leader strikes, be very afraid.
probably the AKM, RPK and various AK versions. I'm sure there are pics of the Nk guards that would tell.
During the Korean War, they used a lot of the PPsH 41 submachineguns in 7.62 X 25mm (.30 Tokarev).
The GI Vets called them the "buzzgun" or "buzzsaw" because at close range they could cut you in half with one burst.
They also produced their own varient (which is quite rare in this country) of the Siminov "SKS" carbine - which is apparently pretty well made, and compares favorably with the Russian and Chinese versions.
The main difference between the AK-47 and the 74, as far as I know, anyway (and I'm no expert on these things) is that the 47 is chambered for the 7.62 X 39mm round (.30 caliber) and the 74 uses a 5.58(?)mm, or about a .22 caliber version of the same cartridge (necked down, essentially).
No doubt the Kongsan (that's what the Koreans call 'em) have kept large inventories of obsolete and captured weapons for the use of reserves, home guard and such.
I wonder if they still use the TT-33 Tokarev as their primary sidearm, the 9X18mm Makarov per Russia, or something else?