Depends how good of shape they are in. They are glass lenses so honestly I wouldn't sand them, maybe polishing with a machine and Ceriglass is all.

I paid $200 for a pair new from the dealer for reference.

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2018 Ram 2500 6.7L Cummins 68RFE
19k miles -Bright White/Black - Big Horn Sport - Crew Cab Short Bed
2013 X5 35D (CEO's) - Born on 5/17/2013 -
82k miles - Alpine White/Cinnamon Brown/Premium Pkg, Sport Activity/Premium Pkg and Sound/20" Style 214/Running Boards