The ones that OldTymeToys posted are all set to print out at the correct size.
I made vector files of a couple standard inserts, one is the design on my Super Punch-Out machine, and the other is the design on my Missile Command (see attachment). Those are also all set to simply print, and they will come out at the right size.
You're printing them wrong then. You need to change your printing options to make sure it isn't squeezing or stretching everything to fit a piece of paper. Look for something to check or uncheck when the print dialog comes up when you tell it to print, or look for something called "page scaling" (you want "none").