Plasticworks (which used to be an IPP franchise) in Surrey has much better prices than IPP (I have only been to the IPP in Langley)...they had a web site - Plasticworks.ca...

I have been able to get many of my off cuts from Glass shops. They often have scraps left over and small peices are just junk to them. They often let it go for half price although you may have to look around for it.