I think this thread has been officially derailed... and for that, I apologise to OP.
In an attempt to bring this back to the point: There is no easy way of going about it. I suggest try speaking about this to your friends, or relatives you can trust (if there is anyone liberal and understanding) or even try speaking to a local "community leader" or someone if s/he is liberal or understanding enough to have a conversation with you about it. Someone who can be there to talk to your parents about your concerns. But don't take any "scholars" word for it.
I can only say the only person you need to justify the hijab to is yourself: not your parents, relatives, "friends", community leaders and whatnot.