Someone here was running a track build with the wing from an M235i race car, it looks OEM (as OEM as a Cayman GT4 with wing risers). IND has it if you're down to pay $4K
https://ind-distribution.com/product...cing-rear-wing. If you're doing it for looks, get whatever looks good to you. If you want downforce, get a wing that has end plates.