Hi, There's a new model, sold from China, very cheap (14 to 18 €) and technically good. Is called LePirate. http://es.aliexpress.com/store/product/Belay-Glasses-for-Climbing-LePirate-Light-Technical-Belaying-specs-Tested-by-proffesionals/1020501_32358135034.html
Cheap Belay Glasses LePirate