Frankly I wouldn't worry about it and suspect that it's been that way for the past 8 years.
I just looked at three, one new, two older--none point straight down. Two are identical to your photo and one swings a bit the other way.
Even the ADC Aneroid Sphygmomanometer box illustration (the box that it comes in which shows the photo of the device) points a bit to the left.
These can be calibrated but you need a calibration kit and while some hospitals may have them, I've never come across one and the kits are expensive.
You could "T" off a mercury unit as all mercury units are precise as long as they were initially calibrated correctly (the only calibration is the marking on the tube) and the mercury is not overly oxidized or dirty. Most people do not realize it but there are leather seals that allow air to pass but block mercury vapor, they are in essence a sealed unit. Additionally all manufacturers (that are still in existence) will exchange an old unit for a new plastic encased glass tube unit that is essentially unbreakable--while the glass will break, the plastic will prevent any mercury leakage. However, even though the above is all true I can already hear the moans and groans of the "deadly mercury" pundits though in fact AHA does NOT recommend abandoning them. (See: Mercury Sphygmomanometers Should Not be Abandoned: An Advisory Statement From the Council for High Blood Pressure Research, American Heart Association
) and frankly I miss the ones that I have used in the past.
Still, if you have a mercury one that is not plastic coated glass--get it exchanged for a safety encased tube type.
This still leaves you with having to either find a mercury one (which I doubt few will ever do outside of a hospital calibration lab) to calibrate against or to find or buy an aneroid calibration kit which do exist.
They are so cheap that nowadays it's probably best to simply buy a new one if you're fearful that it's reading improperly.