If you already have the video file and need a standalone English subtitle file, you can search these popular databases:
Often used to find "forced" subtitles (which only translate non-English dialogue) or full English CC. Family Blood subtitles English
Some versions or trailers of the film may have auto-generated captions, though these are often less accurate than professional subtitles. Where to Download Subtitle Files (.srt) If you already have the video file and