It all depends what type of girl you are looking for and what your budget is per punt, check out:
Diva
Admiral
Hot Collection
Babylon Girls
Barracuda
mainly EE, around the 150-200 incall rate per hour, if you are looking to pay a little more then:
City Butterflies
London Photo Models
A Prov
Carmens Secrets
Allure (would highly recommend this one)
The punting world is your oyster, you may never move back to Bristol
M