Your profile does not specify your gear. But if you want to carry the D800 with 1 lens mounted then you could consider a Lowepro TopLoader series.
I can carry my D800 with 2 primes (1 lens at the bottom of the bag and the other mounted to the camera), plus some small accessories like filters, extra battery, SB-800, remote in my Toploader 75AW.
If needed, I can replace both the primes with Sigma 50-500 OS mounted to the camera and still fit it in the bag.
The camera is gripped with L-bracket is a tight fit but I have no problem so far.
The link you mentioned does not show any details inside the bag, so it is hard to judge / guess what possible items can be carried in that bag.
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