Lee,
On my airplanes of that size, I budget 3 1/2 to 4 oz finished with hinges and horn.  I'd say you're ok.

The last stab/elevator I built weighed 65 gr., 70 gr. with the horn, and had an area of 165 squares.  28 in. span, 7.5 in. root chord.  Completely finished and ready to glue into the plane.

You'd be well advised to hog out at least the stab and put in some 1/16 in. ribs.  It will probably save well over an ounce of weight, not counting the nose weight you won't need.  Since the elevators are tapered cutting them out for ribs will save a lot less weight and probably isn't worth it.