The only ways I see for you to get Windows 7 back on your notebook, is:
1. Buy downloadable copy of Windows 7 from Microsoft's online store
and install it.
2. Get a full copy of Windows 7 on external HDD, connect your external HDD to your notebook and try running Windows 7's installer from there? (I highly doubt it can be done legally?)
3. Same as option #2, but instead of external HDD, maybe copying Windows 7 to flash dongle and try installing it from there?
recommending doing two last methods, I'm just assuming that it can be done.