I have purchased a Source Tek Premium canvas Panel. It is a 1/4 inch baltic birch plywood panel mounted with Claessens #13 oil primed portrait linen. I haven't tried it yet but it feels nice to the touch and I think that I will like the texture. They have up to size 16 x 20 but I believe that you can special order sizes. You can even order the plain birch panels and mount your own canvas. I think that I may do this. I ordered Claessens #13 oil primed canvas in a roll a couple of years ago and I couldn't stretch it. I think that mounting it will work out much better for me. Their website is
http://www.canvaspanels.com.