http://bhlnasxdkbaoxf4gtpbhavref7l2j3bwooes77hqcacxztkindztzrad.onion/retro/last/274.html
But the tape I got was in great condition and it's got cool stuff inside, it has a folded sheet with some information, a mini-calendar for '85 that I don't think I'll ever use because I don't want to ruin its value, and a couple photographs of the artist, Akina Nakamori. Pretty nice little collector's package, I guess.
Don't know if you'd want to, but if you ever do want to buy things from Japan, use yahoo auctions.