When LR is installed it places on your computer a collection of folders, each one for a different camera, that contain the emulation profiles. They are located in Windows 7 at C:/ProgramData/Adobe/Camera Raw/Camera Profiles/Camera. Obviously LR 4 could not include profiles for the 70D in that collection, but I think that if the 70D subfolder from LR 5 were pasted in there LR 4 would use it. Another location where they could be put is C:/Users/Your Name/App Data/Roaming/Adobe/CameraRaw/CameraProfiles. This is where my "home made" profiles are stored and they have always been used by every version of LR since v.2 with no problem.
If you wish, I can make the 70D files from LR 5.6 available for you on Dropbox.