I use Embargo through Globe Growing.

http://www.globegrowingsolutions.com.au/products/brochures/Embargo%20Brochure.pdf

It is actually a 5L container @ 50ml/100m2. Which at 112ml per application twice per year I have a 22 year supply! Since I started using this I went from lots of winter grass to maybe 1 or 2 plants for the whole of winter. Summer weeds are not really an issue with our dry summers so I do an application in late March and then again in August which covers off Autumn -> Spring weed pressure.