I've had several things polished, including headers.
be aware that they get a golden hue when they get heated up (still looks nice)
you can also have headers ceramic coated.
I have all the work done by a polisher...its a lot of work to do it yourself with home-tools.
i wanna say the last time i had it done it was like $100 for headers, s-pipes,caps on end cans and brackets.
the wheels aren't powdercoated, right? standard marchesini matte finish? if that's the case, your odds are pretty low that there'll be a powder that matches "perfectly" (that is if karen's that much of a stickler for perfection).
only way to be truly sure they match is to have the wheels powdercoated as well.
if you go the route of the black frame/wheels with the silver tank/fairing, i think it would look pretty slick if you polish the engine case-covers! that would be a pretty awesome contrast...
...and if you happen to be getting aluminum parts polished, remember to tell that professional polisher first, as the steel polishing process would go through the aluminum like butter... or so I've been told.
headers are easy to polish if you have a bench grinder and several pads. I use abrasive compounds on felt wheels and gradually work up to tripoli and white rouge. Cast parts take a long time. I have not done bike stuff, but I've done turbo housings and that took ages. Lookup metal polishing in your yellow pages if you want someone to do it for you.
I have done all of my polishing myself. Check out strati's site www.ducatipipemod.com and look into the exhaust mods FAQ. There are steps and exactly what you need to do and use. Like he says, make sure all of the anodizing is off of the pipes before polishing, or it won't polish. I like to use sandpaper. Work slowly and evenly and this will get the job done. On things like rearsets etc, none high heat areas, you will probably want to clear coat the area after polishing to prevent rust and crap, or just keep using polishing cloth and touch up the spots that begin to oxidize. I think that polish looks very slick and fast.