Feel free to post your order to
www.bitcoinusd.com. You are not required to deposit coins there. Just wait when somebody interested in will contact you.
I would but I don't know of a way to get from BTC>USD>GBP without incurring very high tolls.
I *think* bitcoinusd also does other currencies.
You might also want to check out
bitcoin-otc.com, which is an "over the counter" market for all currencies - you place an order to sell your bitcoins for Sterling, and if someone with £s is interested they'll get in touch.
...though for a relatively small amount, here on the forum is probably not a bad bet!