Why not try the UK importer, who is currently UKD from memory.
Thorens went for years in limbo in the UK and they've lost most of the healthy market share they once had. To be honest, and judging by the apalling pay in hifi shops these days, I'd be very surprised if you find a long term staff member who remembers these models (I do, but sold very few and the suspensions are different to the 150/160 models I know so well).
One thing about the motor - how come that after twenty years or so it suddenly needs shims? I appreciate the main problem with many Thorens decks in this series was a DC motor with severe servo overshoot (the main criticism), but those little motors should run until they stop....
Please try UKD. It's a small concern and Nick may be around this week. At the very least, he may be able to source a service manual which should explain in depth the setup and alignment proceedure for one of these.
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