Your first rifle posted is an AK-74, late-1980s build. The Type-I bayonet (pre-AKM) you posted with it is also not even capable of attaching to that weapon. Secondly, the "AK-74u" does not exist, either: you have posted an AKS-74u, again, with incorrect bayonet, no buttstock, and the wrong rear sight assembly for that model of AK. Also, the "AK-47" never existed outside of Western military manuals.
AK-1, AK-2, AK (Type-I, Type-II, Type-III), AKM (AKMN, AKMS, AKMSN), AK-74 (AKS-74, AKS-74N, AKS-74u, AK-74M), AK-100-series: '101, '102, '103, '104, '105.
AK-74M









