AtomRC Dolphin Simple DJI O4 Pro Mount

To be clamped (and fixed with some tape) in between the nose and plane body.

I am using this only as an interim solution, but it might be fine for someone.
You might need to cut the foam a bit to allow the nose to be mounted flush if you want this your final solution.
Otherwise, there will be a 1 mm gap.

The 1 mm is "flimsy" but allows for the small gap.
There is a "thicker" variant with 2 mm backside.