Hi, I ordered the women's KEEN Hoodoo III Chelsea waterproof boots in a size 6 online during the recent labor day sale. They are a little small, so I was wondering if I could exchange them for a 6.5 (and get the labor day sale price). In addition, I noticed online it doesn't look like the 6.5 is in stock. Is it possible to have REI order in a 6.5 through KEEN for me? Thank you!