Have a 515 on a 2001 Response with 325 EFI Monsoon. Very near sea level and a perfect match. At WOT it runs 4,950 rpm at 47.1 mph (GPS) with just the driver and has plenty of holeshot.
With 2 in the boat and pulling a slalom skier rpms are around 3,200-3,250 at 32 mph.
With your boat being a bit heavier and at higher altitude I would go with the 525. Because the 2 props are very close in size I would imagine that the wake would be similar.