This unique stainless steel scupper was made by Orcas Marine and Southco. It was used by many boat builders for years but has become scarce in the last few years. It consists of a 2" OD tube, a 2-7/16" OD flanged collar, a 2-7/16" flanged collar with pie-shaped grill, a flexible flapper with a center post, and a rubber plug. The boat scupper replacement tube is 4-3/4" long although it was frequently cut down to fit the hull or transom.
The tube slid onto the two collars and was usually bonded into place with 5200 or other sealants.
If your scupper looks like the one pictured, this is it!