Get form binary data from existing NAST message

Hi,

Is there anyway to get the form binary data from an existing NAST message ? The form has not yet been printed and thus there is no existing pool.

I am trying to get a PDF preview in a custom view of a custom report, and display a print button if the user wants to print the corresponding form. Is there any simple way to achieve this ?

Thanks in advance for your help.

Thibault