Looks like you can get one on DHgate.
That said, you're approaching half the cost of the real McCoy by now... if I were you, I'd treat myself. Even if it's "just" twice as effective at protecting you, it's a small fraction of what an ER would charge to diagnose a concussion and send you out the door.
BTW, Bell probably spends millions a year in R&D, and complies with international safety and testing standards, while the factory making these knockoffs spends about zero, and complies with none, if that answers your question.