It’s been a bit since I read The Book of the Dead, but isn’t there an ancestry option for skeletons to create something like a phylactery at higher levels?

Edit: or maybe even for wizards in general?

Edit 2: “Lich dedication” is an archetype feat with the prerequisites that the user be an expert in crafting, have the ability to cast 6th level spells, and spend 1,600gp to build the soul cage (which deprecated the term “phylactery,” since phylacteries are an active religious artifact in some sects of Judaism).