They have the original props or at least detailed pictures to make accurate replicas from them.I don't believe it's a Matty P.K.E., but I feel it needs to be said for the record:
Sony doesn't have access to the original P.K.E. Meter. Unlike the Packs and Traps, that was a rented prop, and as I mentioned in my previous post, the word was it was apparently stolen some years after Ghostbusters II, and never recovered.
Whatever photographic reference Sony does possess would not be as extensive as any prop photo archives which have been spawned by the digital photography age. Clarity of detail and the volume of photos would be limited by the physical nature of the medium back in 1983/88.