Actually just as a bit of feedback, you have very good taste in requesting Street Fighter 3 as a template for style questions, which is arguably the pinnacle of 2D pixel art. However, have a look at this guy:
Ryu from SF3 is about 110 px tall in his normal stance - with a quality most artists could never even dream to achieve (even if a few frames in this gif seem to be in the wrong order). Really top notch and probably outside the table from your article.
Your average sprite size is 220 x 220 px, which is so incredibly far off the scale in terms of creating art like this it's very debatable if the approach is even sound, even setting aside all questions of payment. KoF did it by rotoscoping 3D models (not that SF3 didn't use tracing as well, just that it was hand-drawn cels) and using a shack filled with Korean slave laborers, and the result really looks less than convincing:
Wooden choppy Terry Bogart here is about 280 px in height, which is closer to your intended size.
Perhaps this makes it clearer that the basic approach in itself should perhaps be reconsidered in terms of scale.
Generally you will find people willing to work under any conditions for any sort of pay - there are firms in Asia specialized on exactly that sort of thing. Only you need to know where to look, and I'd wager it's a bit difficult to expect a careful artist's touch, or proper professional post-submission care.
Edit: Ah, and it might be a good idea to release one of your sketches as an example for the style and level of detail you want - "colorful and detailed" is one thing, but the phrase isn't really very specific in terms of content. If you're too hesitant to do that, then maybe some comparable piece of art.