probably not months until the launch day, because u can't find any iphone 5 parts being sold online right now.
if the back small 2 glasses can be easily changed too, i might do this.
replace the front with black, and the 2 small glasses on the back with black color too.
this will look beast!
Can you send a picture of it? Love the idea, thanks.
Here is a good site for customising your iPhone. Just be aware though this sort of thing voids any warranty you'd have.
https://mendmyi.com/colourlab-v2/iphone/iphone-5/