That is not a base to any normal back seating area. Looks to have been custom fabricated. Everything about this van checks out for common use for refrigerated vans, Dodge, Chevy, Ford etc, save for that odd seat. Again, the seat is not a base you would find in a van from a manufacturer. Has to be custom.
Adding this.
https://reefertekusa.com/photo-gallery/refrigerated-van-custom-design/
This is a company that makes this type of van and this is the custom section. They have a single seat as an option, but even that looks like a manufacturer type.
very nice high res. Visually appeal off the charts.