PhotoStand is SIMBL plug-in for (写真.app)
Tested with Photos 1.0 on OS X 10.10.3.

How to use
  • Download and install EasySIMBL.
  • Download PhotoStand and drop PhotoStand.bundle into EasySIMBL window.

Locate Original File

Small button is added to info panel. This button shows original file in Finder even inside of photoslibrary.

Right clicking this button shows context menu that lists most related files like thumbnails.