It is pretty much the same as mine. Mine has a factory 14" riser and doesn't have the full enclosure, but they are the same machine. They were sold here as a Vulcan, but it is Kasahara iron from Japan. NC Electronic Services imported them and probably added the control and tool changer. I think Compumill had some dealings with Kasahara and may have eventually bought them out.
The part you are missing on the tool changer is a four channel photo diode or photo transistor board that provides binary logic for the tool changer. The PLC takes transistor level signals, so it is a very simple circuit. On mine, there was a separate cabinet with some extended IO modules for the PLC. These are all for the tool changer.
I am using a Galil 2280 and use one axis for the spindle. I am using a Siemens PLC and have enough IO between the two to communicate with simple logic. I have two of the Omron PLC's and the programming terminal if you are interested. I originally bought a backup, but then decided to upgrade. The new PLC is programmed for the tool changer, but I haven't tested it yet. If you want to keep the Omron, you should at least pull the program so that you have a backup or the logic if you need to upgrade. There are something like 20 steps to a tool change, so its really not something you want to do from scratch.