how to get a replacement window sticker

Ask your Chevy dealer.

they said they cannot get it but said there are websites out there that will supply it with the VIN number. I still cant find one.

You can use an online VIN checker to get all your cars build info but I do not know where you can get an actual reproduction of the window sticker which is why I always file mine away in a safe place.

well I bought the car used and there was no sticker

https://chevroletforum.com/forum/vindecoder.php

Car dealers are only legally required to provide the Mulroney sticker when vehicle is new.

Here is a good link to use: https://chevroletforum.com/forum/vindecoder.php