I don't know much about inkscape, I used photoshop to make this map. here's a link to the PSD if you want to take a look:

https://www.dropbox.com/sh/apwcqqtakideyiy/An0C9VVyDM

Basically I took a generic risk map and overlaid it with the texture from some old paper and added text. All the pieces are in the link if you want to play around.