I just went through this on my 2012 MS.
The black valve is 3” and will interchange with a 3” Valterra valve.
The grey valve is another story. Mine was a 1 1/2 Bristol valve and a Valterra valve would NOT bolt in place. The hole pattern on a Bristol brand is slightly smaller and the Valterra would not bolt up. I got a Bristol and it slid right into place.
All of the online documentation I found said the two brands were interchangeable but that wasn’t my experience.
Now if you want to replace the flanges, the Valterra would work.
The grey valve was clearly labeled Bristol Mfg.