my brother does that all the time, he simply downloads the English version then uses a search engine (Same as for torrents? not sure?), gets the subtitles for THAT specific version and adds them up
example, if he downloaded a torrent that said 'version blabla' he gets the subtitles for that specific version, otherwise they would be out of sync and that requires an additional step
sounds like a mess but he doesn't seem to mind.