Any alloy refurbishment recommendations in London or SE area?

Bought my Superb 1.8 petrol estate Elegance with automatic gearbox 2 years ago and have had slow leaking tyres ever since. Changed valves, then tyres and now looking to refurb the alloys. I'd probably buy a new set of wheels but I've just had a new set of Michelin CrossClimate 2 fitted.

Wheels are the 18" Trinities (see pics). 

Previous owner did very few miles and lived by the coast in Northern Scotland. Spoke to a refurb (https://spitandpolish.co.uk) place today and they said the alloy corrosion is getting between the tyre and wheel - so I'm looking to get the wheels fully refurbed. They also offer a 12 month warranty for the work. 

But they're Tonbridge and I wondered if anyone knew of a similar service closer to me in SE London that might also offer a warranty. 

Best, Nick