pip3 install pandas hangs

I've had this same issue on ARM machines using Docker. On my machine python3-pip provided an old pip distribution (9.0.1). So for me upgrading pip & setuptools sufficed

pip3 install -U pip setuptools

Then you can install the rest of your dependencies normally.

I solved this by upgrading the os on the pi, then using the command:

sudo apt-get install python3-pandas

My repositories are now slightly different to in the repositories link in the question, they are below:

deb http://mirrordirector.raspbian.org/raspbian/ stretch main contrib non-free rpi

If anyone's interested, the specs are now as below:

PRETTY_NAME="Raspbian GNU/Linux 9 (stretch)"
NAME="Raspbian GNU/Linux"
VERSION_ID="9"
VERSION="9 (stretch)"
ID=raspbian
ID_LIKE=debian
HOME_URL="http://www.raspbian.org/"
SUPPORT_URL="http://www.raspbian.org/RaspbianForums"
BUG_REPORT_URL="http://www.raspbian.org/RaspbianBugs"

Finally, with the new os I still could not pip install pandas, i left it running overnight with no success