Update.
Thanks once again for your recommendations and private messages.
I decided to take my L.P 12 deck along to Colin Macey in Beaconsfield, a short trip round the M25. I have to say I was instantly put at ease and knew that I had made the right decision as to who would service my deck. I auditioned a Linn Krystal cartridge on one of Colin’s many systems, my intensions were to have a service and a Kore fitted and hang on to my trusted Troika. Despite its age it has very low hours use, sometimes my system was never used in months even years, I once went 8 years without putting needle-on-the-record as my system was in storage for that period. I decided to go for the Krystal and feel that this cartridge will see me out. Colin sent my Aro tone arm away to Naim because of a poor earth, every time I went near the deck I got a low humming noise. This was rectified and also new head shell tags were fitted to allow for the new modern cartridge. I also had to have a new Lingo connector, unfortunately the part was no longer available so a newer Lingo connector and board were adapted. It was also decided that the deck needed a new motor. I was constantly updated while my deck was away and always felt at ease with my initial decision.
The deck is now back home and sounding superb. I would have no hesitation in recommending the services of Colin Macey at What You See And Here.