They Live

The weapons seen in They Live are:

H&K94

As used by Nada(Roddy Piper) but with the foregrip in the "Sten" fashion.

Micro Uzi

Used by Frank(Kieth David)

Ithaca 37

Used by Roddy Piper's character in the Bank shooting.

M16

Used by the Cable 54 building Soldiers.

The original M16, the first version, firing in a 20-round magazine, adopted in large numbers by the U.S. Army in Vietnam. It would later be replaced by the upgraded M16A1 - 5.56mm

Desert Eagle

Attempted use on broadcasting dish by Nada(Roddy Piper)