Hard slipcase for 'The Art of League of Legends' Artbook Vol. 1

Hey guys, so it's obvious I can't find the limited edition anymore. And even if I find it from someone he would want extreme money. Talking about the Artbook by Riot Vol.1 but I was wondering if someone knows how can I find the Hard slipcase that was included with the limited version. I want to keep the book covered and feels like I'm missing something without that cover. So sad that the normal book is not covered... In case any Riot Staff person is reading this, please advice... I really want it.