Unless you are talking about a basic similarity in size there really is nothing to link the 214ST to the 525. If there is .. then please go ahead name them!
GoodGrief, instead of developing the 'D' model Sikorsky would have developed a '77' (or whatever) and taken on something like this. It would have been a 'natural' progression for the 76 in my view. Too late now but credit to Bell for pursuing this ambitious project.