Have you found a solution? I have the same problem. Unfortunately, hauck.de does not ship to Switzerland.

I'd go and ask a bike dealer or even a car dealer.

Enquiries in the Help Centre at hauck.de

Oh dear, how did that fit?
Can't I order individual parts from Galaxus? Depending on the age, could it still be under warranty? Otherwise I would consider with the price whether a new purchase is not more worthwhile or look on Facebook if someone sells the same cheap and take the spare parts from him.