Hello syd;
Based on information gathered on the Web, I have been able to characteize the part numbers you have shown:

6ES5921-1BA11 CPU S5-201A

6ES5922-1AA11: CPU S5-201A Byte processor

6ES5234-1AC11: memory board

6ES5247-1AA11 Stepper motor Input module IP 247

6ES5243-1BA11: IP 243-3 high-speed analog input card

6ES5245-1AB11 : IP 245 valve control module

The S5-201A is a specialized blow-molding controller, with specialized modules that do not exist in standard Siemens PLCs nowadays. From various threads in automation forums, it seems to have been declared out-of-production in 1991.
The CPU, co-processor and memory board could probably be replaced by a single CPU of the modern S7-300 or S7-1500, but I do not know of modules that control valves or stepper motors, or that provide high-speed analog input (not the kind required by platics moulding) in these families of CPUs.
Siemens has a special automation division dedicated to plastics and plastics controllers, that you should talk to for this migration. As recounted here, I had to deal with one of their special CPUs S7-614, and information was difficult to find:
/tf/WW/en/Posts/90008
I suggest you look at the contacts information in the links below and ask them about possible scenarios.

Plastics solutions proposed by Siemens:

https://www.automation.siemens.com/mcms/mc/en/mechanical-engineering/plastic-machines/Pages/plastic-machines.aspx