From the brief research I did on these door tags, the fonts were done by something called an impact printer, not sure all the details or how that worked but these were done on a mass produced scale for the 100s of thousands of vehicles GM made.
This place says they can reproduce the lettering with the correct printer.
https://www.gloveboxoptions.com/shop...-certification
Another one.
https://ecsauto.com/products/vin-dat...72-gm-vehicles