you could make that yourself with some old pc' fans and a 9v battery, seems no protection against eating your hair if its a bit long at the front.
Btw never seen a vents fan, but the goggle system design of vents shouldnt need one as the lens is fully separated from where you breathe.
ive only ever managed to briefly mist the outside of my events for a second or two on a very cold day when having a cardiac arrest.