So let's do a calculation.
For a handheld laser pointed at an aircraft, let's work on the assumption that the eyeball is expose to the beam for 1/1000th of a second.
For visible light, for 1ms, the Maximum Permitted Exposure (MPE) flux is 0.01 W/cm2. (From IEC 60825)
For a laser with a beam angle of 1.5mrad (i.e. a very good narrow beam), the beam will spread by 3 feet for every 1000 feet travelled.
To make the maths easier, I'll round that to a 1m beam at 1000 feet.
Your pupil is defined at 0.39 cm2 = 0.000039 m2, so you will get 0.000012 (0.0012%) of the beam in your eye.
Working that backwards that means you will need 0.0256W of flux into your eyeball to cause damage, which will need a 2066W laser on the ground.
Now a 2kW laser is a bit beyond even ebay.
Or have I got the maths wrong again.
Simon.