If they can stretch their budget (or haggle hard), the Tannoy Mercury F1 Customs are the best at this sort of price-range, at £110.
They're closely followed by the Q Acoustics 1010s at £100 (again, you could try haggling).
If you can't stretch to these, a strong £80 option are Tangent's Evos.
Also look for deals on Wharfedale's Diamond 9.0s (list price £100, but i'm sure they're gettable for less).