$60/yard...but at least it's available I guess.
From the Materials tab on zpacks:
1.42 oz/sqyd Waterproof Breathable Cuben Fiber Fabric New! Finally waterproof breathable cuben fiber is here! This is probably the lightest 3 layer wpb fabric in existence, perfect for your ultralight jackets, bivies and other projects.
The fabric is a three layer laminate with high strength Dyneema fibers in the middle. In our testing the strength, waterproofness, and breathability have all proved to be pretty good. Our jackets for example are breathable enough to sleep in or hike in (if it is cold out) without getting clammy. The fabric is shiny on one side, and matte on the other. Either side can be inside or outside.
Due to the high cost of this fabric it is sold in half yard increments. One half yard would get you a piece 18" by 54". A typical jacket might take about 2 yards. Scroll down the page for waterproof zippers.
Weight: 1.42 oz/sqyd (48.3 g/m²)
Roll width: 54" (137 cm)
Price: $30 per HALF linear yard ($60 per linear yard)