We have just done the same, and decided that it was time to move away from the DigiBlue Cameras. We bought Zu3d (£350 for a small network licence) and 10 webcams. The software is much better than the Digital Blue Software, and it does not need expensive propriatory cameras to work either.
Replacement Cameras are not really needed, our school found a way around it without having to buy a whole new kit
You can still access the camera video files by doing the below instructions. It basicly turns the camera into a external HDD so you can access the files you want.
* Switch on the Camera when itís not connected to the PC
* Hold down the Resolution button on the camera.
* Plug in the camera while still holding the Resolution button.
* You will notice a new drive mounted in your 'Computer' folder called 'Removable Disk'.
* Double-click to open it, then open the 'DCIM' folder > '100MEDIA' folder.
* You can now drag the movies out of that folder and into any location you wish, double click the files individually to view them.