H2W via Amazon offers the Men's Aviator Mirror Lens Sunglasses
with free shipping
. (Non-members can spend $25 or more to qualify for free shipping; otherwise, shipping costs $4.98.) That's $5 off and the lowest total price we could find. They feature metal frames and plastic lenses.
Amazon Prime membership is $79 per year; however, Prime is free for college students for six months, and free for parents and caregivers for three months.