Since it is a very old version, It is very difficult to find information on the web. So what I need is:
1. Information on how to build a system from spare parts (it is impossible to buy a full system today).
2. What is the programming software for the CPUs and the HMI and how can I get it?
3. Manuals and installation guides.
I think this link is a good place to start searching that information:
I don't know if the respective vendor is still selling it. I guess if you contact them they will sell you Centum VP instead.
I dont get it why do you want to buy Centum CS 3000. it used to operate on XP. since XP is obsolete, there is no need to buy this system. You should go with Centum VP; software is more or less same; hardware is exactly same, major difference is in graphical interface which has improved appearance. Software and installation manuals will be provided by Yokogawa.