No one place exists to my knowledge for all three in USA. The closest together is probably Florida. Rotary: Atlantic Helicopters, Ft Pierce (Also EASA school) , Sea: Florida Seaplanes, Orlando or Jack Browns, Winterhaven. FAA IR SEL - easier than the other two to find somewhere between these. Or Alaska - look at Lake Hood....
Or go to Canada and convert the licence after . No TSA, and you should find what you want at Pitt Meadows or one of the other places near Vancouver