I think its interesting to plot them all together, because it shows just how rapid the recent CO2 increase has been - on the Vostok timescale, its a step change.
The scale on each plot is in years; the Vostok one goes back to about 150,000 BP; the others are far shorter. Vostok, Siple and Law Domes records are from air inclusions in ice cores; Mauna Loa is measured.
You can see the data files I used. They are vostok.co2.dat, siple.co2.dat, law.co2.dat, maunaloa.co2.dat.
The original data files are from cdiac who have additional pictures.