The original Pre-cat sensor in my '09 was a heated NTK Air/fuel sensor. It is not so expensive, i replaced mine 2 weeks ago. I had P0171, P2414, P2195 and P0170 codes, the car smelled like fresh human crap for a couple of days, and the smell may impregnate over clothes, so nasty...
The best price i found was Rockauto, at $88 NTK-24353.
Note: Reset code before starting the car after reinstall.