Hi FairDoos - Im also from the UK and I normally go to Yoyotech, if you look at their website they have a fine selection of 22" monitors well under your budget, you can look at the Iiyama monitors and look at their reviews as well.
Or if you can spend a little bit more they have a 24" monitor for £168.21
I hope this helps!
look at acer moniters, fairly cheap, and they're a pretty good moniter as well
I'd get 2 of these http://www.ebuyer.com/product/151386