You can maybe ask around on the Korean forums if anyone has the files for the acrylic cases and have someone cut you something, for the most part a case will be quite hard to find. I know the LZ series all fit them, but they don't fit in standard cases as the F-row is slightly further distance then filco/qfr cases. There are some really nice acrylic pieces out there, maybe if you ask GON if he can help source one.