Exclamation [Q] Readers Hub APK

Hello Folks,
I have a couple of friends with Samsung Galaxy Tab 3's and they have recently noticed that the Samsung Readers Hub has disappeared from their tablet and has been replaced with an Amazon Kindle App. In the process they have lost all their downloaded epubs. I would like to load a previous version of the application onto their tablet as they like using it for epub files. Does anyone have a version that I could install using the APK - perhaps from a titanium backup?
Any help would be appreciated.