You're selling at just about the worst time of year. Nobody has any money left from Xmas and any they got as gifts will have been spent. Plus to be honest you are asking top money for a used item. Usual rule of thumb is that a second hand gun is worth no more than 70% of its retail value IF it's pretty much as new. You've admitted it's got some usage scratches and it's been skirmished so I would say nearer 60% to be honest. £200 is probably a fairer price.
Good luck with selling it though, looks like a nice gun.