Sadly, these RIBBA picture ledges are slated to be discontinued, replaced by a wider depth) version by the name of MOSSLANDA. So buy whatever may be left in IKEA stores or find them second hand on Craigslist/Kijiji.
Love this IKEA hack twin storage bed perfect for toy storage. Click through for the step by step tutorial and supplies list which include a tip on how you can make this bed without a saw! via (Step Design Storage)