This unique stainless steel scupper was made by Orcas Marine and Southco. Not as popular as their 2" stainless scupper, it was used by many boat builders for years but has become scarce in the last few years. It consists of a 1-1/2" OD tube, a 1-15/16" OD flanged collar, a 1-15/16" flanged collar with black plastic insert and cross-shaped grill, a flexible flapper with a center post, and a rubber plug. The 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 sealant.
If your scupper looks like the one pictured, this is it!