You're looking for information on IBM SPSS Statistics version 21, specifically for both 32-bit and 64-bit architectures, and possibly including Amos. Here's what I found:
Keep in mind that SPSS Statistics 21 is an older version, and you might want to consider newer versions (e.g., SPSS Statistics 25 or 26) for better support, new features, and compatibility with modern operating systems. ibm spss statistics v21 x32bit x64bit and amos exclusive
You can find IBM SPSS Statistics 21 and Amos 21 on the IBM website or through authorized resellers. Be sure to check the system requirements and compatibility with your operating system before purchasing. You're looking for information on IBM SPSS Statistics