This Nerf gun is reduced to £5.63 from £9.99 over at Amazon just now.
Suitable for children aged 8-16 years, this Nerf gun holds 6 Elite darts and fires them at distances of up to 75 feet. The rotating barrel flips open for easy loading, and if you pump the Slam Fire slide repeatedly while holding down the trigger you can access rapid firing mode.
The reviews for this are very good too - 43 reviews and they're all 4 or 5 stars. They're so worth reading, since most of the reviewers who've bought this item are clearly NOT children! But here's a fairly typical child-friendly review:
"Grandson loved it and is getting to be a better shot than me. Rapid fire shooting mode was an unexpected bonus."
However you might want to invest in an extra packet of darts, currently on offer at £4.50 instead of £5.99.
With thanks to xennevdl @ HUKD!