Thanks everyone. I figured out an adequate solution, based on researching the Wordperfect suggestion.
I have OpenOffice on this machine, which I installed as a temporary bridge till I could get home to my MS Office discs to install that.
It turns out you can edit PDFs within the Draw program of OpenOffice if you install an extension to import the PDFs called
Oracle PDF Import Extension which you can download here:
http://extensions.openoffice.org/
Draw seems to edit the PDFs about as well as NitroPDF, and is sufficient for my purposes.
I'll see if I can find any free NitroPDF downloads - I have that on my home machine, and it works OK. (Got a free password some time in the past when they offered that as a promotion.)
I knew you guys would lead me to the solution!