have no experience with this, just thinking...that the way to go is to
create a SEBLOD link plugin, which will asynchronously execute a PHP
script that will generate and return the PDF file.
I looked very quickly at the ways, how PDF's are created by the libraries mentioned above and it seems there are two options:
Some libraries e.g. SNAPPY perform PDF generation from an URL of an
HTML page. That can be done with an URL to a SEBLOD list displaying only
one item (by ID) in the desired template and a raw view.
libraries like TCPDF generate PDF directly from coding instructions. So
the PHP ajax script could load the SEBLOD field values from the article
using jCckContent class and generate the PDF directly.
Both ideas, however, are project specific, not easily reusable...