While most, if not all, as-built double-sheathed boxcars were no longer in revenue service by my layout's era, I do have two DS cars that I have picked up over the years. I initially thought I would repaint them into the PRR gray MoW scheme, but it turns out the Pennsy never owned any DS cars. So, while I am not sure what I will do with these two cars I did do some research on them.
The Santa Fe car has a build date on 8-1919, making it one of the last original USRA DS cars produced during/after WW1. The SF had one of the largest fleets of DS cars and with many still in SF's MoW service into the late 40s. This car had wood framing between the inside and outside wood sheathing, and was probably rebuilt with steel framing later in life.
The SSW is not on the list of roads that received some of the initial WW1 era cars. The build date on this car of 3-1924 indicates this was a post-WW1 build, or what is referred to as "USRA clones". Most of these clones, starting around this time, had steel framing in place of the wood framing of the WW1 cars. I do not know if the SSW ever owned one or if this is a fantasy car.
Both DS boxcars are Lionel.