For that kind of service you'd be spending £600+ up front and need to make an appointment for a later date, I'm not sure of anywhere near you but there's a place near me called "
Revs Racing" which are the UK importer for Wilbers suspension products but they can supply other brands such as K-tech and Hagon maybe more..
If you want to keep costs down Hagon would be your best bet and you'd likely bag a full setup for under £500 but if you choose a rear shock from Wilbers it'll likely be around £600 for just the rear mono shock.
Also Hagon don't sell any spare parts which means they can only be serviced by Hagon at their factory, so rather than going back to whoever fitted it they offer a postal service which includes a new 2 year warranty every time the shock is serviced and if they can't service a shock because its no longer in production they usually offer you an upgrade for a reduced price.
Non of those prices include labour, just the cost of parts.
