So it clearly varies by location.
Pulled up my closest one.... $5.39 sandwich only without tax. No cheese/bacon or any add-ons. $8.39/combo meal no cheese/add-ons.
I would honestly stick to oem if I were you. If you want to go aftermarket, be prepared to swap them out. More than a few users have had 2-3+ sets replaced under warranty from carid, ebay, amazon etc after they failed from various issues.