Finding a direct "one-click" link can be tricky because of copyright filters, but several reputable subtitle repositories host these specific files. You should look for files labeled as "Forced," "Foreign Parts Only," or "Non-English Parts."
Subscene is highly rated for its clean interface and community uploads. Finding a direct "one-click" link can be tricky
Finding dedicated subtitle files for only the foreign language parts (Dothraki, High Valyrian) of Game of Thrones Season 3—commonly called "forced subtitles" " "Foreign Parts Only