Super, here are some nice Plarail Enoden videos, except mine
Plarail Enoden Trains Part 1 - with the automatic transfer station from Doctor Yellow Automatic Transfer Station Set
Plarail Enoden Trains Part 2 - nicely filmed stop & go actions, nice tracks and platforms...
The historic car (still running on real Enoshima Electric Railway I think) you're interested in is in both videos, and I don't think it has sound (in the second video it seems added later).
I dont't think it was released outside the sets, but I can be wrong about that. Actually, I dont think that the one from
Enoden Umi No Mieru Tabi Set (502+552) was released separately either. Same thing with the pink one.
Thank you for explaining the reason for 2 female connectors. I managed to fit it into my station, but I wondered why on earth did they do it that way.
I like the road and rail system on your second picture; it's a shame that they don't produce it that way anymore. It would be better than just to put one straight rail in a set here and there...
Oh, one more thing - historic Enoden train from Little Excursion Set is the only one with rear coupler on the trailer car that I have seen.