They made really nice custom-replicas of e-11 for ANH/ESB which were screen-used. I do not know precisely what material they used, others blaster armourers would certainly know it, but here's an interesting link about the specificities of these blasters:
http://www.originalprop.com/blog/movie-guns/star-wars-episode-iv-a-new-hope/
Also here's a comparison thread posted by a fellow membner of the German Garrison:
http://www.whitearmor.net/forum/topic/25183-blaster-comperison-bapty10-vs-bapty20/
And a very recent build thread, once again by a German member:
http://www.whitearmor.net/forum/topic/26834-making-of-tunisian-e-11-blaster/#entry339585