Update: Sold. Good luck everyone!
Raced with this setup for the 2016 year (took DS class on them), and the first couple of events last year in 2017. Been setting in the garage taking up space after I sold my WRX two months ago (building a house). Time to get rid of them. $850 OBO. Let me know if you are interested.
Copied from CraigsList posting:
For sale are a set of four (4) Kosei K4R aluminum wheels from Japan with a mounted set of Bridgestone Potenza RE71R summer tires. The setup also includes TPMS sensors with codes available. Wheels are free from scratches and dents with only minor cosmetic damage around lug nut holes. Original lug nuts available and new valve stem covers.
* Kosei K4R (rare; discontinued)
* Bolt Pattern: 5x114.3
* Wheel Size: 17x8
* Diameter: 17 inches
* Width: 8 inches
* Offset: +50mm
* Weight: 15.5lbs
* TPMS: included
* Bridgestone Potenza RE-71R
* Size: 245/45R17
* Tread Depth: 7/64" (+50%)
Good luck in 2018. Looks to be another good year.