Neither the broadcast sheet nor the fender tag are definitive proof of what actually came on the car. The broadcast is simply a list for production to go by for some options. The fender tag is just there so that dealer service or body shops can quickly identify parts needed for repair. Neither was ever intended to validate the correctness of a 50 year old car.

That said, if you really need a reproduction fender tag a google search for 'reproduction fender tag' will bring up the main suppliers. I don't know who's are the most the accurate appearing. When/if you sell the car I would remove the tag or make absolutely sure in writing that the purchaser is aware that it does not have the correct original tag. You want to make sure that someone three owners from now can't claim that you committed fraud with the intent to misrepresent the value of the car.