I actually think she's wearing a dress and not a skirt/top. I don't know who makes hers, but both Badgley Mischka and James Perse have similar dresses this season.
American Apparel makes a similiar skirt to this one that's probably a lot cheaper, in case price matters. The models in the pics are wearing it on the hips but I have one and it looks much cuter pulled up in a high-waisted style. MK's skirt is wool and this is cotton but you could achieve a similiar look for summer.