amp for sub

Trying not to go over board. I have decided to buy a sub w/two 12 woofers. I will be getting an x-crossover also. I need a good amp new or used under $500 to drive this sub. The sub will be intergrating w/my ML aerius i. The sub is rated at 300 watts. Any help would be great.
I have a very similiar set up except I use three 12" woofers in one enclosure. I use an Adcom GFA-565 with some mods done to it. From the factory it is rated at 300@8ohms and 600@4ohms I have no clue what it actually produces but it is loud as I can stand and I am fairly young.... You should be able to find one used in your price range, the only problem is you may have to buy two of them since they are monoblocks and not many people are willing to split them up. That said I have two of them and use one and have a spare handy, heheheh. Also thick (fewer thick strands opposed to the other way around) copper wire is an absolute must. Which ever way you end up going I use an amazing sub woofer cable that you should try, the company that makes it offers an in home trial so you have nothing to lose and lots of bass to gain. So when you are ready email me and I will give you there number and then we can start a thread about subwoofer cables, well maybe not.....Cheers! Tim
If you have two 12" woofers, I would suggest you run each with its own amplifier rather than one amp with the speakers in parallel. My experience has been you can play louder and the bass sounds better. I suggest you buy a bridgeable stereo amp and a cossover that has both stereo and summed (mono) outputs--most do. That way you can experiment with both scenarios and decide for yourself. The subwoofer addition with an electronic crossover is the best upgrade to improve sound. Enjoy!
Electron Kinetics Eagle 2. Superb low-end control, by any standard. Can drive a 1 ohm load all day long.