I managed to recreate the packages on my 32bit Ubuntu install, I couldn't test them on 64bit, but I did show that it's possible to build them for 64bit:
Download this file: http://files.canon-europe.com/files/soft31335/software/iP1900_debian_printer.tar (7.7MB)
Unpack it on your desktop and grab the
cnijfilter-common-3.00-1.tar.gz file (ignore the deb files), extract this archive and you should get a
cnijfilter-common-3.00 folder. Now you need to go into the terminal and use these commands:
sudo apt-get install libcupsys2-dev libxml2-dev libtiff4-dev
debuild -i -us -uc -b
This should in theory make for you a set of 64bit drivers, both the pimxa ip1900 and the common deb files (as well a bunch of other debs) on your desktop. Install the ones you need and delete everything when finished. If it doesn't work, please report back here.