The easier way I find to install sasl on windows 7 is to use the pre-compiled version from here : http://www.lfd.uci.edu/~gohlke/pythonlibs/
There is a direct link to the sasl librairies here : http://www.lfd.uci.edu/~gohlke/pythonlibs/#sasl just pick the one you need.
Then you install it using pip :
pip install sasl-0.1.3-cp27-none-win_amd64.whl