You're correct, Tom, the real wave gained momentum worldwide in the early 1980s, but, there were some groups around that started much earlier, following the initial release of the Nuggets compilation LP.
The Droogs are most likely the earliest group to be inspired by the sounds captured on the Nuggets comp, if going by their debut single from 1973. By the time the revival era took hold worldwide (1980-81) the Droogs had moved beyond the scene -sort of akin to the Chesterfield Kings progression from strict 1966 garage sounds to more straight ahead rock & roll devoid of their earliest style.
The scenesters and fanzine writers called this style "60s punk" initially; Greg Shaw calling the term to worldwide use. However, the word punk quickly became more aligned to the then current wave of bands following the Ramones, for example, so by 1975-76, punk belonged to those bands, as it rightly should have.
I also find 60s punk to be something that was erroneously tagged - a branding forced to be the defacto term for the obscure teenaged music recorded in the mid to late 1960s. First, the idea that kids formed bands to rebel is pure fiction - that's what the '70s era bands like the Ramones, Sex Pistols, Clash, etc did - to rebel against boring arena rock and tedious musicianship.
Teenagers in 1966, for example formed bands for fun and to attract girls. They were not out to change the world or even rid the world of Herman's Hermits, like Tim Warren mocks in his early Back From The Grave liner notes. And most of them performed the popular hits of the day when they played at dances. Nearly all of them were totally aligned with the current trends of the day. To use the word "punk" as some idyllic concept is ridiculous form a 60's era look-back. The sound of the smallest percentage of 45rpm singles recorded by teenaged groups may have that raw or non-commercial sound we now call punk, but that is the extreme, and not the norm from the era.
That's why Greg Shaw ditched the term '60s punk in favor of 'garage bands' as as 1981, a term which is much better, but again, hardly one that is all encompassing or defining.