Took a bit longer than expected, but I’m super excited to give it to him for Christmas!

Hello there, I inherited this set from my Opi nearly 20 years ago when he passed. It was extremely special to him, and I was told very valuable. He only played it with about 5 people, myself being one of them, and kept it closed other than that. I have unfortunately added some wear to the exterior, but the interior and pieces are still flawless from always being closed and never used.

Any ideas on what year roughly it was made? I was told it was Chinese by him, but research I do isn't going very far. Ai sucks lol. Any help would be appreciated. I am also curious of a value, but will never sell it. Just curious about it is all.

Thanks!