Not going to work so easily unfortunately as photographic shots of products would be subject to different lighting, lens and post processing techniques. I’ve asked our repro company a similar question related to vintage tamiya model kits - same answer. Also, which part of the product do you reference as almost every shot will have ever so slightly different levels of exposure or brightness across a surface. Unless you can find a perfectly uniformly exposed surface it’s gonna be tough. Closest you’ll get to is modern colour matching based on a near mint / non-UV / non-heat exposed sample I feel.
I’ve had about 6 original Octane skin sets, 2 in near mint condition and the closest colour matching areas were on the inside of the case.
You’ll get close with marketing material though, the teal and beet above look like Indigo2 colours to me. You'd get very close if you can find marketing material with colour register marks included...
Edit - Also, isn't the purple Tezro colour similar to an O2+? I've never seen a Tezro in the skin but from photos it looks very close. Though, some photos show the Tezro as blue rather than purple.
Your grey base for the O2+ may be something close to "SGI Darkgrey" aka Davys Grey #555555, rgb(85,85,85)