As I have said before an unusual but not impossible combination of kit. M16A2s which started to come into frontline US Army use from 1986 onwards mixed with M1 helmets, which had started being replaced by the PASGT (Fritz) Helmet some four years earlier. No body armour. Conus based US divisions? Korea? National Guard?
Unless another pack is in the pipeline where are the M249 SAWs? Those were introduced before the M16A2. If you want 1970s/ early 1980s fireteams they really should have M16A1s which look qute different. Late 1980s, suggested by the rifle carried, should really have SAWs.