I've not seen an out of the box solution for that.
The database only contains data about files and not the folders. So you probably end up with a control that checks on file system what folders are present. You might be able to use some of the controls used by the Kentico modules.
You could "cheat" it bit just using the default media select control and ask to select any item in the Folder. And handle it in code.
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For listing you would need to get all media items from the folder. You could query something like:
MediaFileInfoProvider.GetMediaFiles()
.WhereEquals("FileLibraryID","123456")
.WhereStartsWith("FilePath", thePathSelectedByTheEditor;
This would return the files that are registered in the DB. (note this does also include sub-folder items)