Budget solution:
http://www.amazon.com/Shimano-Claris...eywords=double
Amazon.com : Shimano BB-ES51 Octalink V2 Bottom Bracket : Bottom Bike Brackets And Accessories : Sports & Outdoors
will work fine with 9 speed too. Even 7 speed cranksets work fine with 9 speed chains and cassettes.
Next on my list would be a Shimano 9 speed 12-36T cassette and Shimano M592 RD and a new KMC 9 speed chain.
You can keep the costs low until you have to change the brifters.