Actually they are part of a (I think) combined arms brigade in Tibet. Its in the lower left hand corner of the last picture of the set.It looks like somewhere in Xinjiang. Note the desert camo.
Sorry to sound cynical but why is he PLA so reluctant to issue rifle accessories?? These are the special forces already and apart from their new helmet they look no different from ordinary troops (note the lack of combat gloves, elbow and knee pads, so on and so forth)PLA special forces with FAST-style helmet and tactical earmuffs.