That engineering set was painted (or repainted) to be Klingon for ST4, it is where Spock figures out the Whale Songs… And the tube is shown behind a window as the Klingon Crystal chamber. Rich
Thanks for the great pics. I think I see a new project on the horizon. The switches on the communicator look like modified ones off of the an-prt4a. My brother has one of these, it is a Vietnam era helmet radio.