Entex was Bandai's American brand name throughout the 1970s and into the mid-80s. They released three model kits from "Message From Space" and two or three kits from "Battle of the Planets" (Gatchaman).
Amazing to this day, the "Message" kits were only the second model kit series released in the US tied to a specific movie or TV series since the beginning of Otaku fandom. The first would clearly be the UPC "Ultraman" kit series. However, I doubt that the UPC kits had the same distribution as Entex/Bandai . In fact, deadstock, cellophane wrapped of this kit and the other two models from this series are still popping up on ebay.
The ships in this series were for the most part accurate replicas of the ships in the movie (and TV series). Interesting since these were *pre-Gundam.
I remember buying the Comet Fire kit in 1979 and struggled with the hefty $7.00 price tag! That was a chunk of change back then to a infrequently employed high schooler!
*I have always held the beleif that Gundam revolutionized Japanese "Otaku" model kits. It heraled the end of kits with wind up motors and wheels that made them more toy like than display model.