Simple Small Credit Case

Simple Small Credit Case is a standard class 2 lockbox. Upon use, these boxes award credit 201-353.

Source
Simple Small Credit Cases can be obtained through the Crew Skill Slicing. They can be harvested from Security Footlockers on Balmorra (Empire) and Taris (Republic), which requires level 90 Slicing, or from level 17-24 Slicing missions.