If you know the name of the JAR(s) for the libraries you want and they are not present OOTB, you can import them into PRPC to make them available to you.
Another approach to consider might using a Print Driver to perform a 'print to PDF' - you would need to write some extra 'plumbing' to do this of course though. (Or perhaps use Pega Robotics?)
You *do* have the ability to read XLSX (I'm not 100% about DOCX, PPTX) using Apache POI; to extract information you need - depending on your requirement you could write you own extractor facility I guess? (use PDFBox to generate a new PDF? Generate a HTML to convert with 'HTMLTOPDF'?).
NOTES: I confirmed that the PdfConverter is NOT available in my PRPC731 OOTB.
I ran the following SQL:
select distinct(pzjar) from pr_engineclasses
where lower(pzclass) like '%pdf%';
This shows the following JARs are installed that contain classes which have the string 'pdf' in them: