I had the same issue a year ago. If timber portals fit your pistol, one approach is to make a plywood portal backing to the shape you desire, then glue on a facing using balsa or basswood timbers. I was happy with my attempts except if doing again would ensure using sufficiently hard wood. Mine have been standing temporarily in place and when falling forward on the track (when table moved) they are so soft the track puts dent grooves in the wood.