Any stereo speaker experts around here?

[Bugeater]

Or at least someone more knowledgeable than me anyway.

Since I, like everyone else, have been spending more time at home, I'm getting around to projects that have been sitting around for a while. I've been wanting replacement woofers for some cool older Optimus speakers and I'm having trouble finding an exact match. First off, I'm not even sure how to measure for size, I think they're 4 1/2"? Or do I measure the metal frame of the speaker as well?

Also, the impedance printed on the speaker itself says 6 ohms, but the data plate on the cabinet says 8 ohms. Which is it? And the wattage says 65 with a max of 130. So anything in between is ok? Or do I want to look for 65?

Any help is appreciated!

Pics for reference:

[srvy]

This one could work.
https://www.madisoundspeakerstore.co...-woofer/#tab-1