Actually, one should always download, install and run the latest version of the DNG Converter. The current version is 8.3, with an 8.4RC beta also available.
Camera model support is always cumulative with each new version of both ACR and the Adobe DNG Converter. Once a given camera model has been supported, it will continue to be supported in all succeeding versions.
I see no reason whatsoever to use 7.3 at this point.