Neil Smith G4DBN
I have a fair bit of rexolite bar left Gareth, I've had two 6ft lengths of Rexolite 1422 at 1 inch diameter (for 3cm and 1.2cm lenses) and one at 1.5 inch or so (for 6cm).
It turns really nicely:
Happy to saw a bit off and pop it in the post.
I get it from Specialist Engineering Plastics in Grantham.