3DMaster: There are some of them in Vergen, the Dwarven city. So once you go there, you should be able to find some.
erazz: Oh thanks :) Do I go to vergen on roches side? OR is there any dead dwarf i can loot in chapter 2?
Spoilers, sort of...
yes, you can go to Vergen in chapter 2, as part of the other stuff you need to do on Roche's side. I know for sure where there is one, but I'm not sure you can get to it because it's in a part of Vergen you can't get to, but there might be one in a trunk inside one of the houses in the human district in Vergen. There's a dwarf living there, but it's to the right of the gate as you're looking towards town. There's also an elven one on the porch, but that's not the one you want.
You might also try seeing if someone (armorer) has the diagram for it, or you might try looking in the ravines as it might fall as a random drop. Also, if you can't find the dwarven armor enhancement, you might check the shops to see if anyone sells the sahil already made.
Now, I have to see if the sahil that you get in game has better stats than the one that's imported from tw1.