Reader-specific headers

Hi all. So, here it is …
I have hundreds of existing WORD and PDF documents and want to make them available to my clients, on-line. For regulatory reasons, each client should receive these documents with their own (client-specific) header. For WORD files, I use an AutoOpen macro in the file that inserts the appropriate logo in the header area when the client opens the file. I am looking for a tool that will do the equivalent for PDFs. Can PDF Creator do this for me?

I realise that one option is to convert all my PDFs into WORD.

Thanks for your attention.