An idea I used some time ago to get myself out of trouble when the shops were shut.
A bit of a bodge really because you need to glue 6mm and 5mm strips together to make the hook section and then another piece on the bottom of the panel to keep in hanging vertical, but it works provided the lengths aren’t too long and you make sure the glue joints are sound.
Update, used this method in the end but only used 5mm foamex bonded together, all went well and all the brackets fitted in to each other no problem.
Thanks for all the input.
(p.s – Thanks to Dave Rowland for the help with the prints)