Freeware PDF Editors?

[woody649]

Submitting a manuscript for print-on-demand usually requires a PDF, and I'm working on a project that's going to involve merging multiple PDFs into a single file for publication. That means I can't put page numbers into a header or footer within my base manuscript in Word. So I'm looking for a freeware (preferably) or at least reasonably-priced PDF editor that allows creating, editing, formatting, and deleting headers and footers. I know all this can be done with Acrobat, but that's comparatively expensive, and available only by subscription.

Is there anything else out there that can handle this task? I would prefer freeware, but I'll also look at programs that are available as a one-time, "perpetual license" purchase -- under $100.

Thanks.