Suitable Models - An exact match doesn’t appear to be available, but one modeler writes of kit bashing a Atlas ACF 4650.

Reference - Freight Cars Journal #15 by Eric Neubauer is the reference for carbon black cars like these. “Columbian Carbon owns the second largest fleet of carbon black cars.” They were acquired from ACF in 6-7/1968, and were formerly numbered ACFX 47196-47253.

Social Media - The Rail Car History group on groups.io is a good place to start.
https://groups.io/g/railcarhistory/topics

Properly stored, these decals should remain usable for many years.

Acknowledgments - Special thanks go to Susan and the late Wade Griffis, of Jenison, MI, Society of Freight Car Historians, and Ron Roberts of Rail Graphics, without whom this project would never have happened.