I've used Paul Robson for last couple of years. He runs a mobile unit and comes out to you. He is based in Essex but I don't know exactly where you are and if it's too far he probably won't drive out but you could visit him instead.
His website is http://www.biketyresontwowheels.co.uk
and his work number is 07961360930.
If you do speak to him mention that Takis sent you.