Thanks for posting.
I have used some of the Blue Foam, but only offcuts from when I worked in a school.
I almost managed to get the school to add some for me on their order (me paying),
but the technician left & not long after so did I.

I should do as you suggest & track down a supply.
So far the DIY stores have been a complete wash out, only stocking a VERY crumbly
pale yellow equivalent.
