Those are not 240Z mirrors(at least not for cars delivered in the USA). The only side mirror a 240Z destined for the USA came with was a 96301-E4600 on the left door. Any thing else was a dealer, or previous owner replacement...
I have hunted all the corners of the earth for a true Rh version of this mirror, and Nissan never released one, several people have rotated the flag to approximate one, but a study of the base or stalk will show that the angle of the rh is same on the rh and lh examples, proving the rh is the lh used differently.
I have phone made phone calls to every english speaking parts depot Nissan has, and initiated several language proper calls to most of the non english speaking ones as well. I have contacted Nissan North America, The Nissan Museum, and verified every parts book I could find to come to this conclusion.
I will have an avaiable answer or this problem next year-once again, as my car get ready for the street. ( I haven't forgotten, Victor!)
WIll
P,S, both of those in the picture are LHS. for now...