jw,
That shroud is (or used to be) made by BH electronics in Tennessee. They make wiring harnesses and lots of molded componenets for several boat manufacturers. If you contact them, they can be difficult about returning phone calls and such. Unfortunately though, you will have to order one from the Triton dealer and then wait, and wait, and wait. You might call the Triton dealer in Gainesville. I had better luck with them.
Have you looked on ebay? Every once in a while I see one of those on there.