Hi, I'm Japanese.
Like everyone said, coffee is very popular in Japan.
I know Kopi Luwak and maybe most of Japanese who like coffee know about it.
So actually there are many people who want it.
But I know there are also many stores which sell it.
And if you try to sell it, you may as well open the store in the city area because it's expensive and only for enthusiasts.
Of course, you need so much money for it.