Thats a decent price for what your getting. Those are very small speakers though, and they may struggle to fill your room. If you get them and find that they dont fit the room, you can either return them or just sell the Klipsch HD 500's online and keep the receiver.
On the other hand, if you arent going to take the deal and if you need to keep your budget for speakers + receiver at 500, you could also start by getting a pair of floorstanding speakers + a receiver, or bookshelf speakers + a sub + a receiver. You can get some great deals used and end up with a far better system then the HD 500's.