Judging by the fork crown, the sticker in lieu of stamped metal headbadge, and the crankset and brakes, my guess is that there isn't a lot of value there due to classic/vintage status -- I don't think that it was one of Falcon's more expensive bikes. You might be able to buy a similar bike for 50-75 pounds, if you wait for the right one. While I'm no expert about Falcons, I've never seen one in such a color scheme, so it may have been repainted as well.