Some folks just can't deal with contacts. Cheap pair of small wire frame glasses, that you can "adjust" might fit. Or you can take an old pair of lenses out of a pair of used glasses and use a few drops of clear rtv mout them inside the helmet. Might take a little trial and error to align and hopefully it might not be too noticeable behind the visor. Not a perfect option but it can work. I have a pair of "gas mask" glasses inserts for a military gas mask that works too for some masks, uses a rubber strap to hold them on my head, kind of like scuba mask. There are also glasses inserts for industrial reperators that can be found on line, that might do the trick too....maybe.