in the same price range as the bsa r10 (£650 pounds) you could get a air arms s410, weley venom sidewinder (oh i love these guns so much!), hw100 would be a little past your range at £700, flacon praire, bsa superten or a air arms s510. in my opinion, if i had your money i would go for the webley venom sidewinder carbine as these look great and have got good ratings too:
http://www.youtube.com/watch?v=iIaQPMGJiHs :wub: :wub: (the gun by the wsay, not steve price)