Thanks to all who offered suggestions. I found the similar product
'Polymorph' on Ebay at a cheaper price than Maplins ....
I found another source that may be of interest: Middlesex University
Teaching Resources (www.mutr.co.uk).
They're asking =A310.29 for 500g. You'll need to sign up in order to
place your order but it's just a one-pager.
in The City of Light