Have a look at Maserati Quattroporte 3 mirrors.
These are Vitaloni but the bases vary so look carefully. There are some on ebay.
http://cgi.ebay.com/ebaymotors/Maserati-Quattroporte-3-...dZ1QQsspagenameZWD1V
Also some Alfa's used Vitaloni's if you want to keep the same shape. They have different bases, mounted I think on the sides of the doors.
http://cgi.ebay.com/ebaymotors/Alfa-Romeo-Spider-Right-...sh=item140231540750&
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