You can indeed obtain an std code for anywhere you like. Most VoIP providers offer it.As for BT/openreach. They are a world player in the telecoms industry, a presence in many areas, but this shows how the pro independence lot like to pick and choose.
If you want out, fine. But most down here, I would hazard a guess, would say out is out. You want out, then bye bye, no clutching at hand outs from Westminster.
Just remember, Alec Salmond is not your friend.