Yeah, in Europe Single starts at 100 EUR. Dual not under 500 regardless whether 4,1 or 5,1. Shipping from US is most times too expensive.
So for now, I will keep it single-6core and looking out for a miracle...
Thank you all for helping!
...so now I have to figure out what to do with my new "Home"-Enterprise-Server rack with the dual 3,46 GHz.
(everything cleaned, updated and upgraded and complete with cablearm – If only the fans weren't so loud)