Note the two shallow, angled machine tool marks on the left hand side of both action bodies, about ~3" ahead of the ejector screw. Pretty distinctive. It surely indicates the example shown by Badger hasn't been "scrubbed clean" of markings. The flats just to the rear of the receiver rings appears to be pretty close in texture, depth and profile, too.
The finish seems distinctive, somehow, as well.
However, the two butt sockets appear quite different in detail- at least on the left side. Oddly, the finish on EX 11 seems to have had more "clean-up" than E-X 2's in this region.
Done gone plumb 'nerd" on y'all , I reckon! Sorry- it does nothing to define their historical import...
ETA:Oy, buffdog, what's the date of the article?