I don't have any information about replacement parts but you might be able to get some advice from Teleflex GFI. If you want to know what is inside of this device, I have been able to get photos of the compuvalve.

This valve can be quite expensive to replace and it's possible that the replacement compuvalve could fail again. Another option is to replace the entire underhood propane fuel system with another manufacturer's system. New Ford V10 dual fuel systems are more reliable and can switched back and forth between fuels on-the-fly.