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Your bag is authentic so you should have no problem taking it to Hermes and they will tell you if it was treated. It's not like asking for authentication. You'll have a much more accurate idea of what's going on than anyone can suggest by looking at photos. FWIW the body of the bag doesn't look painted to me but the chipping area is certainly odd.
Kellys have gone up in recent years. My Rouge H 28 cost around $4K four/five years ago and I'd never find it for that little now (it does have clochette, lock, keys - expecting a vintage bag to have a strap is a stretch as it wasn't standard back then). But even at that price, actual repainting that made the bag un-spa-able would be unacceptable to me. Good luck!
I believe vintage Hermes bags have their own style & appeal.
I have old & new. They compliment reach other