Oooh, that's a tough order to fill. I haven't seen any yet.
The reasons: 1) not a whole lot of 4k+ cameras out there yet, and 2) aerial photography implies movement: either the subject (clouds) or the camera (as in flight) moves. Thus it's tough to get the multiple exposures necessary to make an HDR still image.
Is there anything inherently wrong with a properly-exposed non-HDR image for your project?
KGAN (CBS) & KFXA (Fox) Cedar Rapids, IA
There really isn't anything wrong with a non-HDR image I suppose, the real importance is finding a true spherical image that can be mapped onto a 3d environment to create an "in the clouds" experience. Short of purchasing the Vue plugin for C4D and creating something, I cannot seem to find anything! All said, it may be cheaper going the Vue route anyway.