I would say that was a tad high unless they are throwing in a decent hard case or have upgraded the pickups or suchlike.
£200 - £250 and you're into decent deal territory, presuming that you like the guitar.
Here are some new prices e.g. Epi Les Paul Standard £349
http://www.soundslive.co.uk/common/query.asp?Name=Electric+Guitars&ID=4
Cheers
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