How to save Subclips and Metadata for Reuse

I'm pretty new to Resolve, but, have had great results so far. My workflow is that I have a lot of relatively long .mov files with some content in them that I would like to extract, but, most of the file is not useful after I have done so. I have created subclips and used them in timelines, and rendered the final product. However, if I delete the original large source files to save space, the clips come up with "Media Unavailable". I would really like to save the good clips and their metadata for reuse, but dump the vast bulk of the original source videos. I'm sure this must be possible, but, not finding it. The best I can come up with is to save the rendered composite video and then clip it up for my new project. How do y'all do it?

Many thanks.