I took the clock to a clock repair shop but they did not work on this kind of clock. They did tell me that the center spring is broken and it needs to be cleaned. Can you tell me approximate how much it is to repair the center spring and to have it cleaned. He said the clock was made in the 60's in Germany. That is what is says on the clock too.
The mechanical movement used in the Linden clocks is made by Hermle. They are the largest manufacturer of clock movements in the world, so I would question any repairers statement that they couldn't repair it. The repair cost would depend on the condition of the movement. Most repairmen will give a no-cost estimate so you should check and see if repair or replacement would be the best cost estimate.