The way I would do it is this: Sculpt the ear parts from plastilina oil clay. Spray paint the plastilina clay with crystal clear or some other coat so as not to degrad the latex in the next step. Then make a mold from mask latex by painting several layers onto the clay until its about a quarter inch think. Once dry, use an X-Acto to cut the mold along the ridge. Clean out the clay and cut a hole to pour in fill, plus a vent. Use straight pins to put the mold back together. Mix knox gelatin up according to jello jigglers recipe, color with food coloring, cool and remove from the mold. Fairly quick wiggly ear tips. Use make-up, gelatin and wax to blend ear tips to real ears.

Here is a page I ran across a few months ago. I hope it helps.

www.scendan.com/lotrears.html