The TARDIS/Police Box should be heavier.
Most real Polics Boxes had, at least, concrete roofs. Some had walls of heavy teak and some were cast iron (though most cast iron boxes were of a different design). Most were made entirely of concrete, with teak doors, and weighed around two tons. Also, the hatch for telephone access in the photo doesn’t look like it actually opens. I’m not a Whovian so I don’t know if that feature ever appeared on the show, so perhaps a non-operable telephone hatch is accurate to the TARDIS.