I have 2 of my Dad's Teacs from the early 1980s back at my mum's house..
But neither have been switched on for approx 20 years..

Pot luck if they will work any more...???

There are youtube videos on "How to" service and replace perished rubber & foam parts & capacitors for tech minded folks..
..and still a few older repair men advertising their services online..

2nd hand serviced and working old cassette decks on ebay are getting more expensive now
as hip trendy young folks jump on the retro cassette fashion revival...