Some honesty...
It's been over a month and you've got shit all of a response. If I were you, I would take the following advice, do it, then give up on this thread.
- Email or phone protec asking them the question you want answering, they are the people most in the know on things to do with their products generally speaking. They will give you the answer to your query, like "hey, yeah we do man, in fact we'll send you one if you give us your address, protec" or "hey, there is a dealer in your state that sells them, get in touch with them, here is the info" and sadly this may also be a response, "sorry man, what you buy is what you get. we don't expect the helmet to outlast the lifetime of the chinstrap, maybe you should have bought the helmet you liked most and not the ceapest"
Maybe you cold die it, or colour it in...
I'm sorry.