Distribute app without source?

[Bill Felton]

Thanks in advance for any insights!

My partner and I have developed an application primarily intended for internal use within our company.  However, we face the need  to expose the app to certain non-employees.
We would like to do so without exposing our source code.
Our targets include users of Windows and Mac OS, but not UNIX.

We are using Python 3.2 and tkinter.  It appears, and limited testing bears out, that py2app, and presumably py2exe, are not options given lack of 3.x support.  PyInstaller does not support the 64-bit version we are using.  

Does it make sense for us to try to use pyInstaller with a 32-bit install of Python 3.2?  Are there other options?  

Any assistance or input will be welcome.

regards,
Bill