I'm not exactly sure what you mean by "brand name", but here are some of the other details associated with the cars (since all three were built similarly).
The bodies were constructed by the German coachbuilding firm Reutter on behalf of the Olin-Mathieson Aluminum division.
One source mentions that at least one of the cars had a Cadillac 331 V8 rather than the expected Chrysler 413.
Stevens, being significantly involved with the Studebaker folks, applied several design elements to the Wagonaire that first appeared for the 1963 model year.
Does that cover it?