You may be able to create a reasonably good looking PDF by exporting all the pages from the document into images and using Scan Tailor to get rid of the margins, and if it is in grayscale, convert it to monotone.
So to sum up the work flow:
1. Adobe Reader: Export to PNG, JPG, or TIFF (preferably something that isn't too lossy)
2. Use Scan Tailor to tweak everything, the program is self explanatory.
3. Again, use Adobe Acrobat to bundle the Scan Tailor Output to PDF, or if you have a PDF virtual printer, that will work too.