servo arms
Yes they do. I just bought 4 of the 3D XL arms today for my JR 8411's. The part # is HAN3578, they are the 1 1/4" arms.
I bought mine from LHS but you can purchase them online through Horizon Hobby. Airwild hobbies also has the aluminum arms for any servos. I have serveral from them for my Hitec servos.