Re: Single 12 for a sealed enclosure.
If you don't mind me making a suggestion, I highly suggest you build a properly designed ported box. In my experience with sealed, it doesn't quite hit the low end the way I would like it.
Also, are you open to buying used or only new?
Amp: Hifonics BXI 2010d
Sub: Old school RE8 (temp sub until I get monies..)
HU: Pioneer MVH-P8200
Front Stage: Morel Maximo 6.5 Components.
Rear Fill: Polk Audio MM651UM
Electrical Upgrades: Big 3, Power Sonic PS-121000 U (soon to be installed)