Hi Bastian,
(how funny, to communicate in English),
of course, I remember. But there are quite a lot of differences between the quality of suppliers respectively their parts. I know some very confident part dealers. They deliver high quality spare parts for favourable prices. These parts are quite cheap but not jerry-built. But [censored] happens, and the sudden end of your clutch cylinder might simply also have been bad luck.
There are repair-kits for cylinders available as well. This is the cheapest and very often a successful solution.

Beste Grüße
Tim