Note, please refer to the forum thread for additional details.
Editor's Notes & Price Research
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Be sure to check the guide to see if the filters will fit your vechicle - Discombobulated
Mobil 1 Extended Performance Filters
Alternatively, the following two are sold by seller "Filterdump" which may be older or surplus stock, but should still be fine.
M1-201 = $7.05 (Lowest Ever)
M1-206 = $7.95 (Lowest Ever)
No longer available:
M1-108 = $8.96
M1-110 = $9.06