Central of Georgia 50' boxcar series 3500-3699 - Anyone know the builder?

[Tristan Ashcroft]

The NARC/PWRS PS 5077 boxcar in the PC version is probably the closest N scale model I have seen to this CG car (ignore that 'PC green' though):

but, but, but...  I thought those were going to be the most accurate cars ever!  Eveeeeeeeerrrrrrrrrrr!

[nkalanaga]

Mark5:  The roof itself isn't flat, but most roof panels of the last 75+ years have some type of raised section on them.  Rectangular panel, diagonal panel, Pullman-Standard's PS-1, X-panel, etc.  These appear to be flat, with no raised sections at all.