Well, it was the text commentary guy who says it was a Commodore 64. Its against Kirks window which those familiar with the film will remember is lit rather atmospherically so its extremely difficult to make it out to be honest. That and i dont have a Zoom option on me DVD Player.
Id be suprised if its a Commodore 64 tho as the film was made in 1981-1982 and although to the best of my knowledge the beloved 64 came out in the latter year i seriously doubt Paramount would have managed to get their hands on one.
Methinks it might be anyone of C= machines as they did all look alike at the time. I definitely think it has the built in monitor.
Im sure its somewhere in http://www.zimmers.net/cbmpics/
Hell, every C= machine is in there!