Edit- I got a couple of questions on this, so I thought I would answer it in the listing.
These are 100% authentic. I have no doubts about it. Price is so low, because of their condition.
Montblanc Aviators Poor-Fair Condition Fantastic Price
These aren't in the best condition so I am letting them go for next to nothing.
The lenses have some scratches that can be seen in the pics. I haven't tried any methods to repair them. The baking soda trick could work. No guarantee...