I have *one* last backplate left on eBay.
I believe we've just about reached market saturation with them, so I don't think I'll be ordering any more when this one is gone.
If anybody still wants one when I'm out of stock, I will gladly share the design files that Protocase provided so you can have them stamped to your heart's content, either by Protocase or by someone else. I don't have a reliable (free) file sharing service at the moment, but if someone wants the drawings I'm sure we can figure something out.
edit: Contact by email is probably best: steve<at>cton.me