You could try orgs such as Human Rights Watch or Amnesty International, with the caveat that they have been accused of favouring one side, or another in particular instances. To echo @Candelestine@lemmy.world what you may consider a violation may not carry the same weight from someone else’s perspective.
Here’s a HRW report from 2021. You could also look at what other non-western countries publish (ex: China), keeping in mind everyone has their own agenda and/or perspective
I had the same issues years before I bought my Canon 7D. AFAIK there isn’t a pcpartpicker.com for photography gear, but I spent many hours reading the forum posts and reviews on DP Review.
The main takeaway I got from them was to spend on lenses as they will stay with you through multiple camera bodies.
Also if you go the Canon route, they used to (and maybe still do) have a program where you get a credit for trading in a Canon camera. It did not need to be working. I bought a dead canon from ebay (~$20), punched in the serial, and I think they gave me over $100 discount/credit towards a body
If you’re going to buy used lenses, make sure you test them thoroughly, a used lens is like a used HDD, you have no idea what the last person did to it. Also, if buying online, make sure you look at the return policy, a lot of places will make you pay the shipping for returns. HTH