This Case web site has sales/spec brochures for many prior models of Case construction equipment. https://www.casece.com/northamerica/en-us/resources/prior-models
This web site has some serial number info. http://www.jicasecollector.com/case-built-crawlers.html
Others here will likely have more info for you. Usually having the serial number and any other info from the ID tag of the machine is the starting point to get the right manuals and other parts.