Platform engineering is the discipline of designing and building toolchains and workflows that enable self-service capabilities for software engineering organizations in the cloud-native era.

Platform Engineering

Naming/versioning things is hard. A <https://calver.org/|https://calver.org/> based versioning system will help in most cases. Just start with the vendor version and append a date and a revision. You might build two things at the same date. Only stick to dates not times.
Take also a look at this Linux packaging policies. Linux distro normally bundle 3rd party software and patch them. It's kind of similar use case.

<https://www.debian.org/doc/debian-policy/ch-controlfields.html#version|https://www.debian.org/doc/debian-policy/ch-controlfields.html#version>
<https://docs.fedoraproject.org/en-US/packaging-guidelines/Versioning/|https://docs.fedoraproject.org/en-US/packaging-guidelines/Versioning/>
<https://readme.phys.ethz.ch/documentation/debian_version_numbers/|https://readme.phys.ethz.ch/documentation/debian_version_numbers/>

Helm packages have kind of the same problem. But Helm supports a dedicated applicationVersion property to outline the bundled version.

At the end it comes down to what information you would like to communicate with the tag. If the vendor version is not that important store it as label in the container metadata 
<https://docs.docker.com/engine/reference/builder/#label|https://docs.docker.com/engine/reference/builder/#label> .