We have a ton of archived photos about every inch of a 38, and here are a few of the area you are questioning.
This is a Sedan, and with the uprights forming the enclosure between the helm station and the aft deck, you really don't need those diagonal braces because there is plenty of structure there to keep things solid.
Here is a factory brochure showing essentially the same thing on the Sedan.
Now when you get into the Express and the Sport Fisherman, you see those diagonals. This one is the Express.
Here is the Sport Fisherman
Here is a nice documentary photo sent in by George Klein, from BONAVENTURE, with excellent documentation of what is actually behind the wood panel on each side of the helm, holding up the roof.
Here is a similar photo from David Hodges, from KATYDID.
These stainless steel pieces serve two functions, they provide a great hand grip, and they triangulate a flimsy extension of the roof that would otherwise be a cantilever subject to flexing. I'd say they're necessary. They generally work only in compression, so you can probably find hardware to make them up with a stainless steel fabricator and stainless end pieces.
Hope this helps illustrate the issue. Like we say, a photo is worth a thousand words.
Paul