Thanks for the reply!
After the installation of SR Runtime and confirming the status of idle from the SR Runtime task bar, neither the EULA pop-up nor a calibration compositor menu option appear within SteamVR.
In attempting to resolve this I have gone into the Vive->SRanipal->tools directory and tried executing the "EyeEULA.exe" which does start the loading screen, but ultimately ends with the Initialization Error.
Additionally I have found that running the "dashboard.vrmanifest" within the tools->SRanipal->eye_calibration_dashboard does add the dashboard menu to SteamVR, however this still ends with the same error as above. (backwards attempt but someone had mentioned earlier executing calibration within SteamVR resolved the issue for them)
I ensured Steam, SteamVR, Unity, GPU drivers, the Eye Pro etc... are all up to date.
I have tried uninstalling and reinstalling SR Runtime and SteamVR several times.
@Corvus @Daniel_Y @Jad