Yes I think you would need a replacement unfortunately
Amazon are normally very good about replacements. I have heard of people who've returned the defective device after receiving the new one but you may have to pay for the new one upfront and then be refunded for the old one when Amazon receive it back. I'd give them a call and see what they say.
I don't see this problem reported very often but I don't think the dead pixels will magically go away.