The Fender Blues Deluxe. I tried that one with a Tele. It gave me a smile from ear to ear. It works great with any Fender guitar, and (semi) hollow body guitars. It also handles pedals really well such as Tube Screamers and Blues Drivers. Plus you get a built in reverb to die for.
He says he wants to spend £300 and in a perfect world it would have 3 chanels (clean, OD, lead) so obviously he's living in dreamy weamy land at that price, but what could do two out of 3 well and respond favourably to a boost or OD? For arguments sake we'll entertain stuff up to 600 or so, in the hopes that he can find it second hand perhaps.