i would like to contribute, just use a regular white candle. using the broad side and just gently rub a layer of wax over the canvas. and you will get a coat of unslightly white wax over the fabric.
so next you just need a lighter. or an gas hob. and just let the flames melt the wax into the canvas.
remember just a light coat will do wonders.
i have done this to my jungle trekking gear and water beads of it really wonderfully, and for a long time. very cheap too.
