rare stuff... I'm not sure if they still made these kind of thing anymore. try eBay. iirc they are quite expensive. You might want to check the Graflex community www.graflex.org if you want more information. They have a forum there and I'm sure they'...
If you can't afford the ones on eBay I just don't see how you can afford what I'm asking for mine, as I go by what they sell for on eBay to determine its value?
You could probably adapt a universal graflok back, anything is possible with money and time, but instead of trying to adapt a universal graflok back maybe you should find a grafmatic back