Old Phosco P111 lanterns and columns in London

A road near Regents Park in central London has an interesting mix of old columns, complete with an interesting assortment of lanterns. Some are the good old Phosco P111, some (like the one on the left) seems like it could be some kind of custom Sugg or DW Windsor product, and then some are a sort of hybrid (like the one on the right) - (edit: they are also P111s, but possibly custom variants made for London). Incredibly, I believe these lanterns all run mercury lamps! I must return with my camera at night.