For period correct mirors on a European car I would select the Vitaloni California mirrors. There are some very reasonably priced reproductions available now.
For a US car there's the chrome mirrors and the Ford/Mercury sport mrrors. There are several versions of the sport mirrors ... those used on the Cougar were popular, but there were versions used on the Pinto/Mustang II/Maverick and the 72-76 Torino that work too. The Vitaloni California mirrors would apply to a US car as well.
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