Ok I probably overreacted. I'll proceed with the install and have the mechanic fix the dent. Thanks.
if I were you, I'll contact the seller to get a good discount. or the seller should send a replacement.
I understand that they are usable but you bought a new headers they should be damage free.
I prefer to get a discount than getting replacement since it's easy fix.
I did the same mistake and bought my wheels from Amazon by USD 1000, there were minor scratches and the seller offer me a refund for USD 400. but i chose to get a replacement since wheel should look nice and defect free.