I had my thick sheet set water-jet cut out of 5mm transparent polycarbonate.
I had the cutter make me 4 sets - so I have 3 remaining.
They cost me £44.06 each which was a bit more than I expected - but they are very nice! If you'd like a set, I'll do one for £44 delivered anywhere in mainland UK.
Email me if interested. Simon.Rafferty (at) X-Eng.co.uk
Alternatively, if you want your own set cut from something cheaper than polycarb - contact Cirrus Laser
http://cirrus-laser.co.uk/ 01444 870 386 and speak to Dave Connaway. Ask for the 3D Printer parts they cut for X-Eng (my company). Say Simon Rafferty said it was OK!
Si