Kudos to you if you can do a true budget build, but it's a hard task to accomplish - it's not just buy the parts and put everything together, there are tons of hidden costs. If you're not paying for it, even better
Focus pumps will support about 530rwhp max, with a BAP 650+...but just cobra pumps with a BAP will do the same. There really is no reason to upgrade the FPDM unless you go with GT pumps, especially with a BAP. A wiring upgrade is gonna be required for that much power no matter what pumps you go with. You'll also want to remove the PPRV which will cost a couple bucks for the right tubing and clamps.
My goal is 550rwhp and I'm already $4000 just recently and am no where near done....and my list includes T56 and similar stuff you have listed (I still gotta get my internals and everything assembled too). Your list also doesn't mention anything about a shifter, so look to spend $150+ on that unless you find a good deal used. Also, good luck running a non-intercooled
vortech setup at 550rwhp+, you'll get a lot of heatsoak.
Remember, there are guys on here that have DONE all this stuff, and we are trying to give you advice when you asked for it