That's a big print!
Since the copyright holding company still seems to exist, scanning the print to reproduce is a bit of a no-no but for anyone who has a similar sized pan of their own that they want to scan in, I would scan it in sections using an A4 flatbed then stitch it together using a proprietary programme (or print the individual A4 scans and tape them together). Getting a print of the resulting file is another problem, especially at the original size! When doing the scan, have a good amount of overlap - maybe 1/4 of each frame - to help the software do its matching.