I don’t know how much information you need. But there is a german company called SHIFT phones who provides information about fair ressources and workers labour condition.
To be honest I don’t talk to friends about the problems with conflict material although many may be still interested in that. I guess I should convince them by the attributes of the device directly. If this is not possible I wouldnot recommend to buy it.
That is why I would like to ask @dainis if he was interested in opening the device not only when repair is needed.