I'm guessing, with respect, most in this forum (which is "Phantom-pilots" after all) think you may be kidding.
In seriousness, the cameras mentioned might require something quite a bit heftier than any drones generally discussed here. In the case of the A7RII - OMG! - that would require a beast to lift, not only in size but also in bullet proof reliability considering that the camera body alone is about 3000USD; a hexacopter (more than four blades anyway) would be needed in case a prop got damaged, if you want to save the camera. I'm sure there are plenty out there, but they may be pricey machines.
One suggestion would be perhaps putting a request on Craigslist (not kidding here) for someone to build a good heavy lifter for you with great flight control stabilization, GPS, telemetry/video link, and a really good gimbal. Be ready to have to get a 8- to0 12-channel programmable transmitter, too. Big investment but it will be nice.