Have you tried the German Market place? Quite a few sets on there all different conditions and prices. I had a set of 18" from there, delivery was around €80. Most sellers willing to post from my experience. Site is in German but use chrome to translate and I just use Google translate to message the sellers.
https://www.ebay-kleinanzeigen.de/s-...nt=app_android
https://www.ebay-kleinanzeigen.de/s-...nt=app_android
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