I don't think Aussino carries suitable bedsheets for 14" mattresses, or at least I didn't manage to find there. You can try John Little, Robinsons and Taka. There are a lot of brands for 14" mattresses' bedsheets, like Kinu, Martex, Hallmark, etc. You can check out Robinsons warehouse sales at the expo for very good bargains, but I'm not sure when is the next one.