Just to add a data point with regard to importing Bottlehead electronics from the US to Germany: In recent years, I received three separate parcels from Bottlehead, without having problems: Mainline, Bottlehead DAC, Bottlebat, and yet another parcel with transformers from Magnequest. Actually, there was even a fifth parcel, a Crack kit (which Eileen was so kind to let me return unbuilt in order to upgrade straight to the Mainline - thank you so much!). Unfortunately, I do not remember all the details. At least in some cases I had to drive across town to the customs office, open the parcel, explain what was inside and pay import tax. I think the Crack kit was even delivered straight to my door. However, having to drive over to the customs office has happened also with other (non-electronis) articles I ordered from abroad, so that is nothing unusual. FWIW, this was all via the customs office in Munich and between 2014 and 2016.
Wishing you the best of luck! It's worth the wait and effort. The sound is glorious!