Darren,

Contact a place called Dalfen Auto in Mississauga, Ontario. They sell rattle trap/fat mat. 200 sq ft for like $100. I have purchased many rolls of stuff from them for various vehicles. It is a tar and tinfoil type of stuff. Does a great job and from what I have found, exactly the same as the Dynamat (did a vehicle once in Dynamat as well).

Here is the link: http://www.dalfenauto.com/