That's really cool. I notice your cars have an interior too. Thanks to all for the help, I'm going to look at the set today.
The car behind my Atlantic is a Lionel 18” car. Lionel made that set around 2007 and it came as a 4 car set, 2 car add on plus a Station Sounds Diner. They come up occasionally. Not a great color match though. MTH has also made a number of 18” cars both streamline and heavyweight in various maroon and orange schemes with interiors and figures.