It looks like Sanctuary is now on Plex TV. I don't know how long it's been up there, but I thought I would mention it. Here is the link: https://watch.plex.tv/show/sanctuary

All seasons and all episodes.

It's also on IMDB TV (new name will be Freevee). An Amazon account is needed for this, but in the past it was an IMDB account, because it was located on IMDB when it started out.

It's looks like the only missing season is 3, but seasons 1, 2, and 4 have all episodes.