Hi! The information below is courtesy of the team that helps post on "event-information" channel for our Discord found here.

It costs around 100-149 coupons/ingots per fragment of Shisui in the event "Time-Limited Ninja Recruitment".

48 x 100 = 4800

48 x 149 = 7152

This means that it would cost around a range of 4800 to 7152 coupons/ingots for 48 fragments of Shisui.