Decades ago I bought MEGA-SCSI from Ese Artists Factory, Tsujikawa himself. Pic https://yahoo.jp/box/6mEK-I
Included are the manual, disk, stickers. questionnaire sheet, warranty and strange portrait saying "You missed badly". Perhaps lucky buyers had something better bundled ;)
Because I couldn't buy anything to connect I haven't actually booted the cartridge NOT EVEN ONCE so I cannot guarantee if it works or not.
Since it's difficult to get anything SCSI connected nowadays I won't use this in future. Anyone interested? Note this stuff is traded around 20000 yen in Japan. I saw MEGA-SCSI+Gouda SCSI bundled sold at 73000 yen oO
The manual is available online and the Google translation works on it http://www.hat.hi-ho.ne.jp/tujikawa/ese/megaman.pdf