hiding imported clips (external hard drive)

I am trying to import clips from old iMovie file structures on an external drive. Don't ask why, but I can't open these any longer in iMovie for who knows what reason. Tired of trying, has been a year long battle. My alternative, unless you are able to recommend otherwise, is to use the FCP X import option to pull in the .mov files so I can import them into FCP X.

Problem is, I have some of the files already present in FCP X, some I don't. I was hoping to use the "hide imported clips" option like I do with my iPhone when importing. However, I notice when I navigate in the import panel to the external drive, find the .mov files, there is no option to hide clips that are already imported. It just isn't there.

Is there a way to get FCP X to scan and look for duplicates in a scenario as such?

Thanks,

-Robert