I hope you find a solution...I've looked into it before. I could only find one place that sells zinc pyrithione. It's considered medicinal so there are lots of rules for it even in the US. I actually want some pretty bad for my own personal soap. At a concentration of 2% (you can't get that level of concentration without prescription in the US), it would greatly help with a skin condition I have called tinnea versicolor. It's non transmittable but I've had it since I was a child and there's no way to get rid of it. But the medical grade stuff will at least make it disappear for a while even though it will always come back. Zinc Pyrithione is, not surprisingly, not cheap. I used to get the selsun blue 2% in Canada off the shelf but can't get that here in the US, the highest anything goes is 1% over the counter.
I really would rather use my own stuff. I used to itch like mad all the time. I've had to go to sensitive skin everything including laundry soap. My stuff is the only thing that doesn't make me itch non stop. Well, except for right now because I've been eaten alive by mosquitos this year and it's only June. I'm to the point that I don't even want to open my front door for fear I'll let them inside the house even during daytime. They're really really bad this year.
I've tried to find a retinoid cream for a while but they're either really expensive or have terrible reviews. I used to buy from the brand The Ordinary for treating pimples and the like. They were incredible. And their price was great. Then covid hit, they changed their recipes and their reviews have all crashed and burned.
ZInc PCA is natural and approved by Ecocert, we have it here called Zincidone - it's a water-soluble sebum regulator, but I don't know whether you can find it in the US... and it may cause irritation to such a sensitive skin as yours...
I personally found that cutting down on dairy foods made a big change. I looooove my cheese, and being in France we can truly indulge (!), but we are now a gluten-free and lactose-free family, and it did make a change in ...well almost everything. Problem: I crave my crispy full-gluten bread with soft creamy cheese on top so much, that when I give myself a break, I go nuts ....and without no exception, the next day, I feel heavy from indigestion + suffer from a bad skin day !!