How much power do you have to power it? I will jump in and suggest that the SI RM-12 is for real and is a great sub in a 1 cuft box. The AF GB12 is also a slam dunk if you decide on that.

Also in the hot deals section is the Adire Audio 12" for $149 shipped and you can get 10% off that if you subscribe to the email . If i was in the market right now that would be hard to pass up. Its a D4 sub and works well in a 1.3 cuft box sealed. You could grab 2 and have room.