In first case sorry, I do not speak German. (only Czech or English please)
I designed and had made Oil catch tank (can) for my S2000. The inspiration was Mishimoto baffled oil catch can, which is sold the equivalent of about €270 per piece. (So that dual solution cost about €550)
Material "container" is aluminum, stainless steel fasteners, the holder sheet steel. It is still possible to cram inside the steel wool as they have versions of those from China, but thanks to filter and strainer it is probably unnecessary. Weight of at S2K is 1.8 kg. Placing as on photo, normally in that area S2000 has cruise control. I do not have it on car yet, but you can see holder on position and mounted. There is no problem to do the holder to other locations or on other car, or just for a single bottle. The price for a single bottle of €125, holder for €20 + postage.
I do not have currently pieces available in stock. After paying the deposit (1/3 price) I was able to deliver it in a month.
accelerated video assembly of container -