PEEK is brutally expensive even in solid chunks; I can only imagine what they get for it as filament. I bet it would make those replacement parts look like a bargain. And Davo is right about the cleavage planes; FDM parts have pretty good strength in the XY plane, but are weak in the Z direction, since all those layers have weak adhesion to one another. When you're orienting it for printing, it's good to take that into account.