If you are feeling adventurous you could try german ebay, they seem to go for less on there.
Otherwise I think you are just in the same boat as the rest of us, keep your eye on the internet retailers in the hope that they may have more to sell before christmas or be prepared to queue up at your local Asda whenever you hear the rumour of stock being delivered.
From a brief phone call I had with my local Virgin shop at lunchtime, I get the impresion they're getting some in tomorrow morning. However, the guy was a bit vague about when they would be available for sale. If you're not doing anything, it might be worth just loiterring around some of shops asking them about deliveries.
if you look on ebay, you may be able to find an auction that is going for 280 pounds or so, with zelda included, just sell zelda on ebay to get 30 quid or so back, and you more or less getting it for 240, yes its a little extra work, but.. its possible.