Elli, it looks like Bernard Frischer can be contacted with the material on this page: http://frischer.org/contact/
I wonder if you would be interested in writing him? My bet is that you personally have the best chance of getting a reply from him for many reasons, not the least of which is your location and connections in Greece.
I would wager that Mr. Frischer may well have more expertise of the likeness of Epicurus as any living person in the world at this time. Further, if he doesn't have an opinion on this himself, he is probably best positioned to ask for help from others, given that this issue is so close to his past research and interests.
Maybe he would be interested in the Facebook page on this topic, and/or a copy of Pan's page (I think I remember he wrote a paper on this?)