Help with choosing an amp

Hi, I've gotten my car, a 1995 Honda Civic, fairly recently and am trying to upgrade my sound system. So far I've bought and installed a Pioneer MVH-X380BT Media Player, and two pairs of Kicker CS65s. I bought one Kicker - CompR 12" Dual-Voice-Coil 2-Ohm Subwoofer which has an RMS of 500W. I completely neglected the fact that I need an amplifier for it though. This website (http://knowledge.sonicelectronix.com/car-audio-and-video/car-subwoofers/how-to-match-a-subwoofer-and-an-amplifier/) led me to believe that I'll need an amp that has an RMS of 500W at 4 Ohms. Is this true, and do you have any suggestions for what amp to get (preferably less than $150, but up to $200 at the most)?
Also, the dude at Best Buy suggested a ported box and I plan to build my own, and suggestions or advice on that?

a dual 2 ohm sub can be wired as a 1 ohm or 4 ohm load, a 500 watt amp rated at 1 ohm will typically be less expensive than one rated at 4 ohms.

a dual 2 ohm sub can be wired as a 1 ohm or 4 ohm load, a 500 watt amp rated at 1 ohm will typically be less expensive than one rated at 4 ohms.

I saw that, but was kinda confused. To wire it with 1 ohm wouldn't it need to be in parallel? How do I wire a single woofer in parallel? Thank you for your reply

it's a single sub but is has 2 voice coils. Wiring both +'s together and both -'s together will put it in parallel. If you check it with a multimeter, it should read about .7 ohms