Ronin, see the gen 703 on the left? Look closely and you can see thin stainless steel wrapped over a brass core. It's visible on the edge that would be closest to the case, where the tiny folds overlap.
Only gen crowns are made like this, 700 - 702 - 703. The 704 is "monobloc" so it's carved from one piece of steel, hence no need for steel wrap over a brass core. It also has much thinner walls than a 703.
MBW "703" crowns have nice thick walls, just like the middle one in your photo. Hint: They're great raw material for using a dremel and file to put a bevel on the case side and mimic a 702.
So IMO you have, left to right, gen 703, MBW 703 and gen 704.