It's going to be a little bit of time before I can get a photo of the other side, but I can further add a few details. The boxcar in the photos came to the NYSW during the years that they where operating the Rahway Valley, and what we cannot see is that the side facing the street has the boxcar door open with the wall of glass windows showing. Both the boxcar and coach 599 (which had been in Central Vermont paint) recieved NYSW paint prior to being moved from Little Ferry to the Rochell Park station, at about '91 or 1992. The air conditioning system in this car was replaced in the late 90's, hence the different roof top equipment. The roatery vent fan and door cut into the end of the boxcar can be seen in both your photo and the 2010 photos.
As for the hand rails, the NYSW in the mid 80s had a few movies filmed along the line, and boxcars used for the films had handrails and roofwalks reapplied to back date them for the films. This may or no be the case here, but it is possible. On several storage boxcars that are around, you can see that they where reapplied hastily, for film use only.