I own a Fuji, but would have to say that if you were to stick with Nikon or Cannon.  You would find a great camera.  The underwater housing is going to be hard.   Usually the lower priced (under $1000.00) won't have the demand for specialty items like that. 
 
By the way I love my Fuji s602 
I wanted the Macro features with the zoom (210).  Take note of the minimum focus distance.  Most cameras are about 3"  My Fuji is 1mm 
 
Jason 
		
	
		
		
		
		
		
	
		
		
	
	
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