I actually gave you the wrong plugin. (Although the one I did link too is very good as well. HERE is the one that I use. (I've had it for so long I forgot where I originally got it from... ) Also I did a very quick example of a parchment effect for your map. This is just running the parchment plugin taking your map and thresholding it to black and white and then using "select by color" to select all the black and hitting delete to erase it. I then placed this as a new layer onto the parchment base. Hopefully this will give you some idea of how it could look. Of course you can play with layer styles and opacity to get different results.

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