Yes - but not just the '70s. VW introduced the 11Y nnnnnnn chassis number system for the 1966 model year, so any VW made since then will use it.
Australian VWs of the time were manufactured in Melbourne (NOT made in Germany like US Beetles). Therefore, as well as the third digit telling you the year, the SECOND digit should be a '9' which means Australian-made. After 1968 this doesn't apply, as we went back to CKD kit assembly after that.
There are a few other places on Beetles that also have date stamps. Have a look at the wheel rims, under the hubcaps; there will be a little 3-digit date stamp in a small 5mm circle (eg - 6-67). There will also be a date stamp on the back of your speedo, and sometimes on the underside of the front blinker chrome covers.
Phil74Camper ·