I know I can't get the best for that price but thats all I can spend. Ive found some but I dont know if they're any good:
http://www.amazon.co.uk/gp/product/B0079G2Y2A/ref=noref?ie=UTF8&psc=1&s=computers
http://www.ebuyer.com/522698-cooler-master-cm-storm-ceres-400-white-edition-40mm-drivers-in-line-sgh-2010-kwta1
http://www.ebuyer.com/620615-turtle-beach-ear-force-zla-gaming-headset-pc-731855060061
http://www.amazon.co.uk/E-3lue-Headset-Headphone-Earphone-Microphone/dp/B00G65MIU8/ref=sr_1_6?s=computers&ie=UTF8&qid=1400780751&sr=1-6&keywords=eblue
Strict budget of £20. No more.