I am currently working for a company that does retrofit double glazing using optical grade acrylic sheet in 3 mm, 4.5 mm and 10 mm thickness's. There are always a bunch of offcuts of varying sizes that would be suitable for windshields, Nav light covers, Inspection covers or ???? Occasionally there are panels with scratches that would be suitable for blowing canopies. If any of the Australian members are interested and can organise to pick it up in Canberra, ACT, let me know and I can fish out any pieces you want and get a price for you. Most bits seem to get priced at A$5 to A$15. In sizes as mentioned above. You can either leave a message here or PM me on call the office on 02/ 6255-7220, speak to Sian, pronounced Sharn.