Is there any ways to reduce vibration on a racket without buying a new one?
My idea is to put a very small layer of overgrip (using the extras I have cut off) on top of the cone. (like the ns7700 cone). I don't know if that would work or not. Does anybody else have good ideas?

You can reduce the tension, add an overgrip, or get a thicker string.

That being said, I thought the ARC10 had great vibration dampening.

wrap thick or multi layer of overgrip
lower tension
use softer type string
i'm yet agree that thick string reduces vibration, i thot it's the opposite

Well if you play well at that tension might be problematic to reduce the tension. You can probably just wrap it up in grips and reduce it that way. Or simply go for another racket.

Well I'm not sure about the think string...but people would usually recommend BG65 which is soft anyways....the only real exception is BG70PRO.