Mine are chrome. IIRC, back in those days the mirrors were dealer installed so there could be a lot of variation from car to car.
Looking at the early UK magazine articles (i.e. Series 1 cars) most seemed to have a single drivers side chrome one. Later cars over here seem to mostly have a pair of Vitaloni Californias. My '74 car had a pair of hideous rectangular ones fitted when I bought it - very rapidly swapped for a pair of Vitalonis which suit it pretty well.
I agree with David and Dom. Early was single chrome, later was Vitaloni's. Mine had the chrome one replaced by a rectangular thing, car now has 2 Vitalonis. I think I can get away with it even at a concours since my car is one of those late Series 1, early Series 2 cars, it already has a bit of both. Not that 2 Vialonis is a big improvement over no mirror at all, they are badly positioned on the doors and do not have a lot of mirror surface. Gerrit
Gawd those are awful mirrors. I'd much rather have the Vitaloni's my Alfa has, but I think the big mirror's would look even worse. Oh well... Trade-off's
Like everyone else has stated,Series 1 had one single chrome rectangular Cromadora Astro although I found another one and put it on the passenger side as I have a narrow driveway and need all the views I can get.Series 2 had the Vitaloni