The jersey is genuine, it's a premier range jersey, you can tell as it has the team helmet on the jocktag. The premier is not faked so that's all good. As for the signature, I cannot authenticate it I'm afraid. Did you get a certificate of authenticity with it or were you present when it was signed?
As for a price, well the jersey, unsigned, would be worth somewhere between $40-$70, new they are $110. If the signature is real then that's where the money will be, this is just my opinion and anything is worth what you can get for it, I would look to get around $120 for it, maybe a little bit more.
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