Hi Dave,
Ironically, I have a New Hope & Ivyland R.R. boxcar also by KMT and what's odd is that the number is the same as your boxcar,#800912. The difference is mine is black with yellow sliding doors. Never thought I would see another NH&IRR boxcar around.
Mine came as a gift from a friend and fellow modeler of The Raritan Valley Hi-Railers train group, because he knew that I was a fireman, about 4 years ago, on that railroad, on #40.
It is a consolidation, Baldwin built, in 1925, and a great loco. The gift was primo since it brings back some great memories of working the engine & many other jobs that were needed to be addressed (maintenance). I have the original box and the car is in great shape. Really like yours though.
Steam Forever
John