This sounds like a use case for the feature request tag replies, not just topics, where it’s been noted that:
…so you might chime in to upvote that request.
I’m not a developer but I think a non-tag approach would probably make use of the post_custom_fields table that’s used by plugins like the Custom Wizard Plugin. Incorporating a custom post field into the UI — for selection, display, searching/filtering — sounds like a pretty substantial plugin project.