yes that's the ones, and you can see how the tongue of the shroud fits into the slot in the bobbin, giving the greater creeepage and clearance distances.
Cool. Since the laminated cores are bigger than toroidal, i'd probably want to use it in an external power brick type supply. Say I wanted to power a small amplifier for use with computer speakers, a design like this should be suitable? I show an earthed core/fixture since it's easily done and won't cause earth loop issues so might as well be added