Surrounds, and center that match the GMA Europa?

My conundrum is this. I have a HUGE room something around 24x35 and I need to build a system in this room. What I want is a music system with HT ability. I have heard nothing but praise for the Europa’s, so I was thinking that those would be ok as mains. Are there any surrounds ($400) and a center channel ($350) that will do well with the Europa’s. I am not sure what receiver ($400) to get at this point either so I am open to suggestion. If anyone can solve the puzzle of small budget big room I would be greatly appreciative.