anyone have any pointers for sourcing variable thickness glass (or any durable transparent material). having a need for a couple pieces roughly around 1' x 6' in size and variable thickness of ~1/4" at top and increasing to ~1" at bottom. It'll need to be durable, comparable to automotive side glass (not windshield). A quick internet search was not helpful, looking for any typical use for variable thickness glass, suppliers, prototype manufacturing, material recommendations, etc... Thanks!