As of now, the OM-1 camera from OM System is capable of the announced external ProRes RAW recording, as the required firmware updates for both the camera (v1.1) and the compatible Ninja V and Ninja V+ monitor/recorder (AtomOS 10.76) have now been released.
OM-1 with Atomos Ninja V
The recording of 12-bit ProRes RAW video in DCI 4K resolution at up to 60fps is supported. According to Atomos, ProRes RAW clips can have their white balance and ISO values adjusted after the fact in Apple Final Cut Pro.
The OM-1 mirrorless system camera features an stabilized MFT sensor and offers 10-bit 4:2:2 internal recording up to 4k60p and 1080p240.