Well, first of all if you are planning to stay in the UK, you also have Imperial college, ESCP, and City university. If you want to go over the channel to France or other places on the Continent you have a TON more choices.
I'd suggest having a look here:
https://rankings.ft.com/businessschoolra ... ement-2011As for application, your GMAT is a wee bit on the low side, if you could boost it by 40 points or so, it would help a LOT. But anyhow, when you DO apply make sure that you mention your intention to return to the family business (especially if it's a big one) schools LOVE candidates who will take over the reins of an already successful company.
And the same goes for an MBA.
And in the meanwhile (until your MBA) do what you can to GET INVOLVED... joining clubs, leading them, taking your time to volunteer, etc. It will be very helpful when you apply.