There are lots of receivers in the "under $500" range that would be fine. Denon, Onkyo, Yamaha, are a few more I would look at..

Purchase the receiver based on features and don't get all hung up on wattage. Keep in mind the difference between a 100w and 200w receiver is only 3dB's, you won't even notice 10W.

M80s VP180 4xM22ow 4xM3ic EP600 2xEP350
AnthemAVM60 Outlaw7700 EmoA500 Epson5040UB FluanceRT85