I used to have three cases just like that. now I just have one. Sold the other two on eBay years ago. I found them at a mom & pop video game store (closed down now) in Chicago back in the mid 1990's. I also remember buying the original TG-16 cd player attachment used from the place for $80.00. This was back when the 16 bit era was dying out and the newer consoles were the rage...
Anyway, what was cool about the case was it had custom cut foam that fit the original TG-12 console, 2 controllers, turbo tap like a glove. Due to age though, the foam started falling a part and crumbling away.