I only just saw this message (I'm running 3 months behind!)
I am not Arch, my names Tim.... I'm sure Arch would be very grateful for this information though (not sure who he is sorry)
If you are Arch, owner of Euro 931, I noted your posts on the German language board about hardtops. You might want to check out VX220 (or Opel Speedster) hardtops. There is one on EBay UK right now. I have confirmed that a Speedster softtop will fit a Tesla Roadster. It appears that VX220 wheels will fit, but I have not confirmed. Let me know what you find out.