Does anyone know who carries these?

I dont' know of any manuf. that sells the nickle brass but Federal loads it. Try contacting Federal directly. When I had my 458lott, I made some nickle brass up by using .375h&h brass.

Why would you want the nickel brass? Just curious.

If I had to venture a guess I would say because they are said to be more corrosion resistant.

Easy way to distinguish loads--- ie, brass and softs then nickel and solids.