You know, as odd as this may sound, the black clothing she wears reminds me a LOT of the under armour we wear for track. O_o;;
Under armour topUnder armour bottomThose are just to give you an idea of what I mean. I don't know what her back looks like, so the top may work (maybe if it's covered), but at the least an idea.
You can find this at pretty much any sporting goods place, though if you aren't careful, they can get a bit pricey.
As for the rest...it appears that you have most of it. Really all that is left is your shoes, gloves, and the actual costume itself.
For the actual costume, try and find a pattern that resembles your costume (you can even ask the people at the store for some assistance and they should be able to help). My suggestion would be to use a sundress (or summer) and adjust it (depending on how confident you feel).
For the shoes...If you really want to get acurate, chances are you're going to have to build off an actual shoe.