That's a huge room, are you really set on tubes? I'd get a big pair of maggies and a 400+ watt solid state muscle amp and a pair of subs. Then invite a bunch of friends over for the concert. I hope your neighbors don't live too close. Oh yeah get a tube pre if you need something to glow.
what to buy first
If I am buying from scratch and cannot afford to buy an entire system at once. What should be purchased first? Speakers, Amp/Pre-amp, etc?? Currently I have music with an inexpensive home theater receiver and small B&W speakers. I have music but I will be replacing those items and putting them in another room.