Wire harness radio is there replacement ??

Hello
I have now fulfilled my dream again since 3 years with the purchase of an A8 Mod.95 .

So now my problem the previous owners has become navradio with DVD etc. built what's okay. I took the part out today because I don't need it (have a mobile navigator) and wanted to install my Blaupunkt radio.
Sh... wass there were almost all cables separated with plugs and against clamps and other colors were replaced the pure chaos I can only say.

So, anyway, I'm starting to disassemble everything (cable lettuce) and look for what might have been my question. Is there a replacement wire harness that I put on still over the serial cable again and thus have serial status again?
Or maybe. someone like that in a butcher/cellar, etc. lying around and would it sell me?

I haven't seen if it's Bose or Nokia system,