Used, but in good condition, Thule Rapid Traverse Foot Pack (4 total) 480R. These will work for cars without a factory roof rack and Thule's AeroBlade rack system. I had these on my 2008 Toyota Camry and they looked slick, but have a new vehicle now so no longer need them. You would just need the appropriate fit kit for your vehicle.
When purchased through the Thule site, or licensed dealer like REI, these items sell for around $200. I'm asking $140 obo.