Here is a variant of the taller extruder mount designed to work with an E3Dv6 instead of a hexagon. Sourcing an actual 6mm extruder mount plate is a pain in the ass, but I do know of two locations to find them if anyone needs one.
Why not just print the extruder plate?
Aluminum flexes less than plastic.
In what situation would the hotend flex the plate? 
And a 6mm ABS plate at 80-90% infill, sandwiched to the extruder… tough to flex.
Extremely high speed printing. At lower speeds it wouldn’t flex the plate. At 400mm/s and above, it would be a concern.
Hmm… ok. I don’t think i’d ever set the speed that high, but i guess its possible.
Filastruder has them…
Looks like they just have the plastic one or the aluminum bulldog mount.
