Some feedback for the OP and thanks to the info suppliers.
I recently got the 200-500 lens, I used this threads info to outfit my case and carry needs. Maybe a basic review may help the OP.
I got the Think tank 150 case - great! There is room for the lens hood at the bottom (inverted) and as advertised the camera/lens fits perfectly (D7200 no grip) I can have my RS-2 200PL plate on the lens foot plenty of room rotated in the shooting position (Thinktank put thought in this one).
I decided on the Blackrapid RS-4 strap, it is excellent, for my mounts I got the Blackrapid RS-2 screws for the lens tripod foot w/plate and one for my camera w/plate when using my smaller lenses. When strapped to the massive 200/500 the balance is great (camera and lens mostly horizontal). The RS-4 can do right shoulder or left. It feels like you are not carrying the weight you really are, its so good I took off my neck strap for now and may not use it again when not carrying the big lens (using my favorite 18/300) the RS-4 is simply a joy to use.
I did get the speed belt as well, supper comfortable to wear it should really help if a hike is required to a "spot" it will do exactly what Hark indicated. Hope to give more feedback after some more time with it.
Hope this helps