I have a few original window stickers saved off on my PC. This is one from a ragtop 400 car.

I made my own window sticker several years ago, and display it on cruise nights. The Firebird window stickers were smaller than the regular Pontiac window stickers, but I used the large format (more room to write). My own window sticker can be seen on my web page, and shows the "Pontiac Engineering Car" heritage. One of the things that's VERY hard to do is to get the font to look like typewriter font. If you look carefully at an original window sticker, you can see that some letters are weighted a little heavier on one side of the letter. For instance, an "M" may have the right most vertical thicker than the left part.

I played with the character spacing to match an original, and I also had to drop in commas using a different type font, in bold face, to match what the original window sticker looks like.

I learned all this from Dan Rather a few years ago.