Sadly sensors are all bundled up with the rest of the camera, because a Schmidt camera (corrector plate like your objective, adjustable primary mirror, sensor directly in the primary focus with it's back facing the scene) can easily get a very wide aperture (e.g. nicely matching a CMV12000 with a fairly tame single glass up front and a tame mirror in the back, plus a slab and a plano-convex lens right at the sensor to flatten the field/focus, yielding 400mm f/2.0, though that's with the focal point dead center in the sightly over 800mm tube; still around f/2.4~f/2.8 brightness to the full f/2.0 sharpness (near center, but even at the corner you need a monochrome sensor to feel the mushiness)).

Celeste's prosumer 8~14" (aperture) Schmidt-Cassagrain typically support replacing the secondary mirror with a camera mount to get that much shorter focal length (IIRC around f/5).

Might be nice with one of those very narrow studio video camera bodies (e.g. Black magic has some); the catadioptric nature means you can carry even the very big ones on your shoulder (I'd highly recommend a gimbal if used for shooting from the shoulder).