You are correct that you cannot use a the typical rivet gun to install stanless steel rivets.
It depends how they are made. I used an average Stanley brand rivet gun of the type you find in various hardware stores. It has done 304, 316 and monel rivets. The thing to look for is that the arms of the gun are made from top-hat section steel, and not cast alloy of whatever type it is they use. The cast ones break and the jaws often crack too.