these two eye glasses are better than standard reading glasses for our HMD projects,
they have greater magnification (more then +3.0 dioptrien, mostly the max value of standard reading glasses)

http://www.sehhelfer.de/index.php?searchparam=LUL0489&cl=search&send=Suchen
magnification x2, dioptrien +4.0, ca. 16 Euro

http://www.sehhelfer.de/index.php?searchparam=LUL0486&cl=search&send=Suchen
magnification x2,25 dioptrien +5.0, ca. 16 Euro