Well, John, you're in luck! Mira and Sirius are both binary systems, where one of the partners is already a red dwarf. Sirius is about 2.2 times the Sun's mass, while Mira is somewhere between 2.2 and 3.7 solar masses. So, given that, the pictoral essay you just looked at should be about as accurate for Sirius's future evolution as it is for Mira, though the time-frames for Sirius will be somewhat longer due to the star's smaller initial mass.
With regard to Sirius's position on the Mira essay timeline, you could take Sirius, itself to be at approximately the point mentioned at Stage 2 or 3, and its companion star to be at the position depicted roughly between Stages 4 and 5. The discrepency between the relative stages is because the time-frame between the final evolution of Mira's companion to white-dwarfhood and the start of Mira's evolution off the main sequence is depicted as being shorter than it probably was for Sirius and its companion. In other words, Sirius's companion was probably substantially larger and more massive than Sirius is, and so completed its evolution off the main sequence before Sirius began to even leave the main sequence. In the case of the Mira system, I assumed the two suns to be relatively close to the same mass, and thus that they would evolve off the main sequence at relatively close times. My assumption, of course, could be wrong, but the photographic and reported evidence I have seen suggests that I am right.
One thing that may be of interest to you regarding Sirius is that the star was described as being reddish or orange in ancient texts dating back a few thousand years. Whether this was due to the white dwarf companion still being in the stage of red giant (doubtful. I doubt that a star could evolve from AGB giant to white dwarf in only 5000 years) or being in the final stages of blowing off a last ring of un-burnt hydrogen (more likely--hence my suggestion that the companion might be in the state depicted in Stage 4 of my essay) is not made clear.
