My brother in law recently visited the Smithsonian Air Space Museum and returned with a photo of what looks like a Sikorsky S43 baby clipper being restored at the Dulles location. I had been under the impression that the only Sikorsky flying boat left was the VS44 at the New England Air Museum near Hartford.
I am aware of at least one Short Sunderland at the museum near London and at least one of the Japanese planes at a museum in Japan, and one Consolidated Coronado at the Pensacola air force museum. The Catalina seems to be much more common out there at museums but I'm not aware of any that are in operating condition.
Does anyone have a better inventory of what still exists out there of these planes? They actually built quite a few of the various Sikorsky models.