welcome to the site mate. i reckon you will find what you need here there is plenty of blokes with the know how and experience. i dont know what type of material you guy's use over there but lighter dosnt always mean weaker when it comes to what you use in a chestplate (or cutvest). i use a material from a mine its a type of filter cloth and looks like a white fire blanket when layed out but 2 or 3 layers of it will stop any tusk. ive had a couple of the collars since 2005 and they are still going strong. i tried the 2 layer and the 3 layer.
here is a pic of the plates i use