Got my 550 with pods, ran like crud. got an air box, and almost quit trying getting it in, but I did it, and man was it worth it! Bike looks good! much better than mine did, and now currently does ( but it's inside now and is about to get a new life)
If you're still looking for a brake caliper let me know, I'm almost positive I have one in the shed, probably needs rebuild, but I'd give it up cheap! probably worth it. If you're interested shoot me a PM. I love letting old vehicles live again! and stopping is key for the owner to live!. I might have other stuff that could help you out, but i'd have to go through boxes of stuff.
GOOD LUCK! she'll probably run if its got good compression and you give the carbs a good cleaning, check your ignition and all that good stuff.