GearXS has these oval shaped blind spot mirrors, on sale via eBay, for just $4.99 w/ free shipping.
“Increase vision and eliminate blind spots. Make driving safer for passengers, pedestrians, cyclists, and motorcyclists. Have peace of mind and stay safe with the 2 Pack: Oval Shaped Blind Spot Mirror. Place each mirror on the side mounts to ensure that all persons, automobiles, and cyclists can be seen in those dangerous blind spots.”