Here's a picture of one cars from the NHD #55 four-car set:

I'm surprised this digital photo existed, since the set was released before there was general Internet use. Still looking for an online pic of the Bev-Bel cars, but they were released before the NHD cars so it will be tough.
UPDATE: The Bev-Bel item numbers for their Life-Like limited-run PC and CR X72 boxcars were #10002 and #10001 respectively. They described the product as a "50' Evans Single-Door Boxcar". No pic of the CR car, but here is the PC version:

As you can see, you're better off painting/decaling the models. There was a good PC X72 weathering article in the June 2001 issue of MR.