Not exactly what I was talking about, but these will get you started:

Base rope:
http://www.cheaperthandirt.com/ROPE305-1012-584.html

Prussic Knot Rope:
http://www.ems.com/catalog/product_detail_square.jsp?PRODUCT%3C%3Eprd_id=8455 24441775679&FOLDER%3C%3Efolder_id=253437430287 5257&bmUID=1151246751518

Instructions: (near the bottom)
http://www.sailingteam.calpoly.edu/knots.html

Hope this helps
Steven

PS. For reference when shopping...I think the base rope needs to be atleast 9mm and the prussic rope(cord) needs to be 4.5 or bigger.