Try this site for prices
and for Keane
I'm not sure how up to date this site is.
A good record collectors shop is Vinyl Exchange in Manchester, but they don't list this record.
As for selling it, I'm not sure, because you won't get anywhere near the list price by selling it to a store or dealer. Also record prices vary wildly, depending on latest fashionable artists or recent deaths.
I've got a fully autographed radio promo CD of The Happy Monday's Rave On. At one point it was worth £60, but I went to sell it after the band had faded and was only offered £5 for it, so I took it back home.