PRR #1,
Please, I did not take your advice as a insult, I welcome the helpful information.
Before, Old Goat provided the link with a color photo. of the actual D&M box car, with the same scheme, as my purchase, I had no idea, if a prototype car existed at all.
I searched the inter-net, but I did not find any D&M prototype car similar to my purchase. Instead, I found three color photos. of D&M prototype box cars with different paint schemes and in each photo. it was difficult to visually see any end markings and that is what lead me to believe that these cars were either D&M 'Home Track' cars, or FAMOUS Lionel 'FANTASY' cars, or a Lionel goof-ball.
And, until Old Goat's link and your info. of D&M never owning PS-1, 40 ft. box cars, that I did not know who the builder of the prototype car was.
I know, Lionel, also, is famous for their Pullman-Standard-1 box car designs, but due to the lack of prototype info., it might just have been possible that D&M had cars built by P.S., or used PS-1 building kits.
Thank you,
Ralph