Good news everyone, I phoned with Heidenreich today:
the cases are in production, 9x black & 1x alu blank for casius are confirmed
invoice should arrive tomorrow
lead time ~ 4 weeks, confirmed delivery before Heidenreich goes into holidays (4th of August)
Also thanks go to casius & xtrmnt, who relieved me from paying Paypal fees. I'll donate the fees to Twin-X (hosting costs), when the financial details are processed.
Edit: Invoice is paid.