As the JCrew site says, "perfect for warmer weather" -- JCrew's stretch cotton sateen suit comes in two colors and is comprised of four mix-and-match pieces: jacket, dress, pants, and cropped pants (no quite sure how office appropriate cropped pants are -- perhaps take them out for the summer bbq). The jacket and both pants come in black and champagne colors (the champagne jacket and regular pants are pictured right). The dress comes in black, champagne, and light chartreuse (yellow).
The jacket is $168 (here), the dress is $128 (here), the regular pants are $118 (here), and the cropped pants are $108 (here - available online and via catalog only). All made from cotton.