He's just looking for deep bass without lots of space.
12 inch is the way to go, 15 is too big for a small box to play deep notes.
The Dayton and Peerless are great subs, but a bit pricey, and the peerless does not have the best power handling if you have a big amp. The Dayton is pretty awesome with the Alumimum cone and big coil,
If you shop carefully, you can get a good car sub for not too much money AND get good sound quality. You CAN use a car sub for Home Theater if you get a good sub. IMO Don't get a speaker with a dome or dust cap, because they can come off or get loose and rattle with high power!
A Sony 120 or 121P5 Sub in a 1.25 or 1.5cu ft sealed box will go really deep and sound good, the ones with a solid cone and NO dust cap is what you would want. Plays 20hz bass well.
It doesnt matter whether the sub is car audio or home audio, as long as it can take the power , have long xmax. home and car subs have similar parameters.
There are plenty of 12" car subs that would operate in 1.5 ft3 sealed, Try rockford fosgate, JL audio, Mtx, kicker solobaric and other good branded subs, Dont bother with the cheap ones, They're not worth the money, They wont be as good as the more expensive ones.
I also recommend the Dayton RSS315HF-4 12" Reference HF Subwoofer 4 Ohm , it would work well in a 1.5 ft3 box. I'm about to buy 2 myself. And it's reasonably priced at $138- at PE.
I second aznboi3644 in rather using the Titanic. Two other worthy drivers in my opinion would be Creative Sound Solutions 12", recommended volume is 1,165 cubic feet or the Eminence Lab12, that has a recommended volume that is even smaler still.