for 300-500 you will get yourself a nice amp. i suggest some nice A/B power for them and try to find a 2 channel amp to power them at a higher ohm load, but keep the 300 rms per.
I can offer up a US AMPS USA-200. It is a great 2 channel amp that is perfect for the setup. Down side is that you will draw a decent amount of current with a A/B amp on those subs but it will typically sound much much better.