PLM is installed co-res with CUCM and CUC.
If you mean the standalone PLM image, that one I'm not sure if you also need a valid contract to download it, but if you're logged in and you can't, then most likely it does.
No one here can help you if your CCO is not associated to a contract that entitles you to download from cisco.com, you'd need to engage your SE/AM for assistance.
HTH
java
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