Curiously the seller on ebay doesn’t show any sprocket holes of the Terminator strips which would almost certainly show the digital audio and categorically date it later than the 80’s.
The dolby S.R track is possibly 5.1 but looks like stereo to the naked eye, It would have to be laced up into a projector to know for sure. I miss my days as a projectonist!
I would love to get my hands on an original print from 1984, I don’t know how many were ever made back then and very few if any would have made their way over here to the u.k.