500 is currently the hard cap for enhancing spells I believe(at least it is for Phalanx/Stoneskin/En-spells/Embrava) and you can easily hit like 511 without this earrings.

Merits(16)
AF2+2 hands(18)
AF1 Legs/Potents Pants(15)
AF3 back(6)
AF3+2 Feet(15)
AF2+2 body(15)
Colossus Torque(7)
Fulcio Grip(3)
Olympus Sash(5)