I would take a serious look at Aperion
Given your budget I would take a very serious look at Aperion. In terms of quality and bang for the buck, you certainly can't go wrong considering Aperion.
With Aperion there are multiple packages , or you can custom configure a system to fit your needs. Given the amount you have to work with you could have an excellent setup. You can call them and discuss your room, they are very knowledgeable.
I personally have an Aperion setup, my feelings are you could spend a lot more and get a lot less in terms of quality and value when you compare with Aperion. Their customer service is excellent.
As for receivers, I would take a look at the Pioneer VSX-23TXH Elite or the Pioneer VSX 1019 AH-K. The VSX-23TXH was just reviewed here. The VSX 1019 is getting good reviews as well. Both the receivers can be had below the $700.00 you have set aside, shop carefully you will find some decent pricing on both.