Welcome
As Frenchie mentioned, SMD (Southern Motor Developments) in Newhaven are just down the road for you. Brent knows his stuff and is a decent chap too. He's looked after my scoob for years, wouldn't go anywhere else for jobs I can't manage myself.
What is wrong with the caliper you need replacing? If its stuck pistons, then several companies will refurb them good as new.
