This finish is Matt Silver Plate, and its a little high maintenance as its not sealed like my other silver finishes so it never tarnishes. Why? I find the lacquer process alters the silver color and makes it more pearlescent white, and it looses its soft silver-ness.
To care for this colour, keep it wrapped in the acid free tissue (provided with your jewelery) and in a snap lock bag inside my tin packages. Its the air that tarnishes it, so eliminating that will help. I have also heard that anti tarnish strips are fabulous. Popping them in the snap-lock bag with the silver works wonders.
I have seen them listed on Ebay USA and I am sure they are available in Jewelery supply stores... just not here in Australia!