Hello, I searched and couldn't find subtitles in pure text format for these videos.
As you said, the site I quoted provides only subtitles in sub format, which cannot be readily read by a text editor like notepad.
However, a quick search on google turns out some promising results:
As far as I can see, there are programs that claim to be able to convert a sub file into srt format for an end user. It's a process similar to doing OCR on a scanned book. But I didn't bother to check myself, so maybe you need to invest some of your time trying to find out which program can best fit your needs.
Thank you for your reply! Yes, I know about these programs too, but It's a very long time until the .srt text will be done, so that method quite complicated.