Simply bootstrap a standalone Python. From the end-user's perspective no system python install, simply unzip and run. The python build standalone will be used as the interpreter instead of the system install for creating the virtual environment!
https://github.com/indygreg/python-build-standalone/releases
- In install.bat move the base install Python to a suitable location that will not be moved by the end-user.
- Simply edit install.bat Python calls to the base install path
- Run the install.bat
If this is suitable I'd be willing to submit a PR.