Alien Contamination (1980)
An astronaut, a government agent, and a police detective investigate a South American coffee plantation controlled by alien pod clones from Mars. Stars Ian McCulloch of ZOMBI 2 fame.
The film is more commonly known simply as "Contamination" but this Cannon Films version "ALIEN CONTAMINATION" may be in the public domain.
Love this review of the Alien knockoff. Maybe it will inspire others to bring this to the full riff treatment.