Due to agreements with the patent holder, Cephalon, that were made in 2005-2006 several generics manufacturers are now allowed to sell generic Modafinil. I have found confirmation that the manufacturer Teva has begun selling generic Modafinil, though I haven't seen news about other manufacturers. However, the article also, says that Cephalon is a subsidiary of Teva, so perhaps this won't have an effect? The Modafinil patent is set to expire in April 2015.
Her price isn't that great, even with the Reddit discount, so I'd say something like p>0.2 would be enough to push me to buy from the Silk Road or one of the other online pharmacies instead.
I had never heard of Silk Road. Now I understand the appeal of Bitcoins.