The surrounds should match (Don't really have to but it's going to look different, which is enough for me to make them match). but the subwoofer doesn't.
$200-$300 isn't going to get you anywhere for a subwoofer. It might do surrounds to match your set, but for a decent subwoofer you're going to have to spend $500 minimum IMO. Anything less isn't worth it for the long run.
What size is your room, and how much music/movie (%/%) watching will you be doing?
SheepStar