Where do i find the 'legs' mentioned in the instructions .....???

referring to the circular black pieces in the pictures, used to fix the pcbs to the box(using the little black screws from the JS) ......... one of which is apparently drilled all the way through and takes a bolt to secure it to avoid having 250volts flailing about on the loose if glue fails ..... they're not included in the parts list and my dismantling of my JS didn't produce any???

I guess you are talking about the parts that should be printed from the "PCB Legs 01.stl" file.