Here is a link to Longacre mirrors which are of the warp type used in racecars. I've raced with these and find they provide very good coverage and since the distortion is in only one dimension, the brain seems to handle the reverse image well:
Longacre Racing - Online Catalog: Electronic Wheel Scales, Gauges, Pyrometers, Chassis Setup and More!
The "replacement" mirror avoids the cost of the brackets, which are probably useless in a street car.
Here is a link to the multipannel "Wink" mirror:
G-Force 5 Panel Wink Mirror Kit - SafeRacer
It has no distortion of the wide angle view. Disadvantage is that it is large and blocks a lot of forward/upward visibility like signal lights.
Some folks use convex mirrors, but I find the distortion troubling.