Zoomed in, that looks pretty horrible. Lots of light and dark noise in the scan, wobbly edges because of it.
I'd export it into a format that you can import into your favorite PCB creating software, put it as a background image, and redraw it.
If you want it to look exactly as it does on the original boards (or as close as possible), then I'd bring it into CorelDraw or Illustrator as a background image and redraw it manually.
You can drag it and rotate it to get it lined up and sized correctly, and correct for any image warping.
I just exported it in PDFCreator (free) as a TIFF. PNG will also work, but don't use JPG because it just adds noise.
Here is an Electronic Survivor Shot PCB. I had one to repair that had water damage, so I just duplicated the PCB, moved over the IC, coil, and photodiodes, and replaced the other parts with new. In my case, I cut this on a vinyl cutter so there was no fill. It didn't take terribly long to do this.
Steve Greenfield AE7HD