Hello,
There is only three brands in the market, SUBAL, NAUTICAM and MEIKON (SEAFROGS). The first and second, aluminium, the 3rd polycarbonat.
The Aluminium cases with ports for the lens you have to spent at least around 3500 if you have already have the lens for their ports. The Seafrogs cost you around 400 euros. I have the seafrogs, its very nice, you have some restrictions on commands but its easy to resolve. You just have to pay atention to maintenance before each dive, exactly as the other ones.
And I bought that one because if I floodade I still have a lot of plafond to buy a new body comparing with the coste of SUBAL and NAUTICAM.
Here its a link of some photos.
Cheers
CArlos