Thank you for your informative reply, much appreciated. I wonder why someone would steal this, doesn’t seem very useful for a bomb, unless maybe combined with more radioactive materials?
There was a case decades ago of someone planting a radioactive source underneath the driver's seat of someone they didn't like. The driver eventually got radiation sickness.
But it's also possible the radiography unit was stolen for the heavy shielding which could be sold for scrap metal.