The Belles Aria is well within or below your price point. You could sell the S2s and use the proceeds and change to buy some towers.
If you like the S2s a lot and want to get an integrated that doesn't cost more than the speakers, I've found Rotel integrateds and receivers to be great values.
If you like the S2s a lot and want to get an integrated that doesn't cost more than the speakers, I've found Rotel integrateds and receivers to be great values.