Yes, such a camera was shown in the 1938 Graflex catalog. It is listed along with the other Speed Graphics as the 2 1/4 x 3 1/4 R.B. The descriptive paragraph reads " The 2 1/4 x 3 1/4 unit, made up of a new all-metal 2 1/4 x 3 1/4 revolving back fitted to the 3 1/4 x 4 1/4 camera chassis, admirably combines economy of operation with added versatility. In fact, almost two to one direct magnification is obtainable with this unit when its generous bellows is used in combination with the short focal length lenses listed for it. Supplied with a "Graflex Back," it accepts interchangeably the 2 1/4 x 3 1/4 Graflex cut film holder, plate holder, film pack adapter, film magazine and the Graflex focusing panel."
This camera is only in the 1938 catalog but apparently came out in late 1937. It was replaced by the 2 1/4 x 3 1/4 Miniture Speed Graphic in late 1938.
The R.B. listed for $80 w/o lens or focusing panel but with one cut film holder and for $113.75 with a f 4.5 5 1/2 inch Kodak Anastigmat lens.
Quite a rare Graphic!