Patrick,
If you ever find these drop me a line. I do think B&O got them made years ago. One of the Syndey installers is probably your best bet. Forgot his name....
Radio parts sell the female din connector, so do bosscom. You can get a clipsal slimline or standard wall plate with a punchout that fits. Some electricians modify or supply unusual wall plates. Tivoli HiFi or Carlton Audio have access to some usefull stuff. Masterlink fits an old AT&T socket so the bosscom female masterlink connector fits in.
Hope this is some help.
My place is overrun with B&O cables...
Cheers, Beoaus.