[Dakota773]

Not sure if your missing or broke the actual scupper or the rubber flap that closes the opening.  If it's the rubber flap, that on is easy, order rubber from Grainger and cut to fit ($10).   If it is the actual scupper frame and it is anything like my 98 31' open it is a Tiara specific design.  Two pieces, one fit from the interior and one fit from the exterior (slide into one another).  I Call Brian Kane at Tiara and had had it in a week. 

If it is the same, you'll need to make a jig to extract the existing broken pieces that are 5200'd in.  Plywood and some threaded rods w bolts cut to fit worked great in addition to a heat gun and some patience.

Let us know if you need any more guidance!