While waiting for the real deal I tried some ESD-Packing materiels I had lying around. Turns out none of the clear foils and bubblewraps are of any use in this project. That was to be expected.
But I found a foam in a IC-packing that seems to be slightly pressure-sensitive. I have no Idea where this stuff came from nor where the ICs were bought. But of course I will follow that hint as well. But experience tells me foam won't be as reliable as foils as it will degrade over time.
My delivery is still on hold due to some parts which are not in stock yet. Meh. Need them for another project.