You can probably buy and alter some normal clothes to make it.
I'd suggested a white track suit top, with some blue fabric or....I can't remember what it's called, but it's for trims and stuff, I'll edit this post later when it comes to me, or fabric paint might work.
blue pants shouldn't be too hard, and a blue bandana shouldn't be too hard to find or make.
edit: Bias tape, that's what it's called, it shouldn't be hard to glue or hand sew on.