Lars,
You're welcome.
These can be repaired, especially when the only problem is that the stalk/arm doesn't hold in the right-turn direction anymore. Only two rivets inside the basement block are worn out and can be exchanged by 2.5 mm bolts.
Please search the website here. This has long ago been described how to do.
Contact me off-line per PN please for a German version; I am afraid I do not have any English printout of this procedure anymore.
Best,
Achim