Morphy Richards RC202 Radio Cassette Recorder?

Have had this in storage for years - kind of working when I tested it but could do with a renovation. Volume control slider jerky, producing bursts of static noise. Cassette compartment door misaligned and I can feel sticky patches inside - works if you hold it shut but not consistently. Release catch sometimes sticks. Otherwise in working order; aerial not broken, picks up radio, alarm function works, plays tapes (subject to above concerns), works with AC adaptor - not yet tried with batteries. White casing has yellowed but feel this could be used for many more years if it could be properly cleaned inside. Can anyone recommend a repair shop? I'm in southwest London. Thanks.