It's less trouble to just replace the backplate. They are something like $7.50. Some people just let the broken part dangle in the wind. Some people have fastened the piece to the firewall.

But the AX has a bolt on steel/plastic/brass one that works well. It will not break. It just bends out of the way.

You can always bolt a Tower Hobbies 46 remote needle on the OS 46. The Tower needle will bolt right on with no mods

I fixed one with some .060" aluminum sheet to make a bracket that bolts on the backplate screws. Then the needle valve piece was fastened to the aluminum bracket with 2-56 butten head allen screws.