As one of its daily deals, Woot offers the Harris 36" x 84" Blackout Grommet Panel Pair in five colors (Grey pictured) for $26.99 plus $5 for shipping. That's the lowest total price we could find by $5, outside of the mention below. They're machine washable and feature six grommets per panel. Deal ends today.
A close price: Amazon has them for $32.79 with free shipping for Prime members.