7JuRock
http://www.7jurock.com/store/index.php?act=viewProd&productId=324
http://www.7jurock.com/store/index.php?act=viewProd&productId=324 7 JUROCK] is one of the few places to get an aftermarket windscreen for the EX250F anymore. It comes in a number of options and is very affordable. Screens are custom-made and ship within 7 business days.
This is the 18" model in dark smoke(73% tint). This one has a 'lip' molded into it, to deflect even more wind for our taller rider. The screen can be ordered with or without this modification, as it is custom-made to order.
Installation was a breeze, fit was dead on, and the fastening holes are clean; no rough edges, no distortion.
With the stock windscreen, the wind hit our 6' 3" rider about mid chest. At highway speeds, the new one hits about the middle of a full-face helmet visor, with a little on the chest and shoulders. This does, of course, make the rider a bit warmer than before, which is one of the reasons for getting a tall screen in the first place