As stated, you can do it yourself with MarineTex. Simply mask off the area you want to texture, scuff it with a red scotchbrite, apply the MarineTex about 1/8" thick then, when the epoxy is just tacking, use a tongue depressor to lift the peaks in a random pattern. Let it cure. You may need to use a bastard file to knock down some of the really high points but man is it an awesome texture. I applied it on a B&C stock about forever ago.
Rather than file down the peaks, either put on a rubber glove or take Saran Wrap and coat it with release agent and gently flatten the areas when the epoxy is firming up