Hello Peter,
Pictures of an original interior on a 3rd series B20 are very difficult to find.
In Italy there might still be an original, never restored, B20 3rd series. Best would be to ask the Registro Aurelia (but your friend should join the Registro first ...).
Best I can do is show you pictures of my 3rd series interior, which was however redone at the end of the nineties - for a very meticulous owner! It is in the original colour of nocciola. Cloth in this color is also now quite difficult to source.
Hope this helps.
Thanks Sebastian, this was for my Aurelia. Will post some progress updates and final pictures.
Alistair