WTB: High power 12" subs

My amp will take anything i throw at it…Im making a box that uses up my spare tire well and i planned on getting 2x12" woofers rather than keeping my 4x10" woofers so i want to get the 12s before i make the box so that i can make the box to spec for the 12s. Im looking in the 400watt RMS and up range.