is there anyone that knows where you can get fairly inexpensive display back ww case for vintage movements (0-12 size).

Hi Darren,
Frei & Borel offer several ww cases with display backs. These are primarly for modern movements but may be able to fit your needs. I always wanted to put a vintage movement in one of these but haven't had the time yet. This is a great catalog for other watch material even if the cases don't work out.
http://www.ofrei.com/index.html
Jon