Can I list objects in my GCS Bucket by contentType? Or by suffix/file name?

Question

I have a GCS Storage bucket that is very large (tens of millions of objects). Over the past year or so there have been a handful of files that were uploaded with the incorrect MIME/content type, and those files were not processed correctly due to the incorrect type.

I would like to identify those files so they can be re-uploaded with the correct contentType so they can be processed correctly.

There are two ways that I think they could be identified without simply listing all objects in the bucket (due to cost of listing all objects):

1. List objects by content type. I know what the content type of the incorrect files will be, so if I could just perform something like WHERE contentType then I could easily get the files

2. Luckily, all the incorrect files will have the exact same file name. So if I could list files that have a "suffix" (as opposed to the supported prefix query) then I could get all those files.

Anyone have any ideas? If neither of these solutions are supported I guess I will have to list all the files in the bucket and spend hundreds of dollars.