Amp for sundown z v.2 15" sub?

What would be a good amp to power a sundown z v.2 15" subwoofer? it needs to be under 450$ and i would really like to be able to keep a stock alt. and only use 1 battery. I have a farad cap... idk if its any good considering its a pos scoshe cap but whatevs. any help would be appreciated. thanks!!