"HARU is a free, cross platform, open-sourced software library for generating PDF" - so why not use it from Squeak.
 includes a first rough version of a binding for the free Haru PDF library . It's not fully complete but usable to start printing.
Use at your own risk and feel free to help moving it forward
(MIT License). The squeaksource repo is read/write.
See examples in class PDFDocument to get started. Since it uses
FFI an external library for your platform is required .
Place it next to your SqueakVM.