Epstutz

Hi I have a question regarding authentic keys for Lincoln keys from 1972-1974. I have one key, however i have two keys. One has u.s stamp just under the keyhead. And the other says usa. is the usa key right for the time period? Or was it made later?

Hi. may be off topic, but i am looking for a vintage 1970s stutz keychain. Does anyone know where i can find one? Except ebay,..