Dual Blade Mastery book in Cash Shop Gone??? -Post RED Patch

Can someone please confirm that mastery books for Dual Bladers are gone in Cash Shop because I can't seem to find them, also if they are confirmed that they are gone, can someone tell me where to get "Slash Storm 20" Mastery book as it is what I need right now. Please help me ASAP

Dual Blade's 2nd/3rd Mastery Books are available from Taeha in Secret Flower Garden for 100,000 mesos.