The result of playing with filter effects in Inkscape. It could probably be better but if anyone wants to use it you can. Download the file and copy the filtered object into your work; this will also copy the effect and you will then be able to apply it from the Filter Effects dialog. You may need to tweak the parameters to suit your needs: in particular, you will want to alter the frequency of the noise and size of the Gaussian blur elements to get the right scale.

As the preview image says, this is not just a raster image embedded within a vector one: the SVG file contains a description of the effect which can be scaled arbitrarily. The shapes it is applied to can be altered and the effect will update.