Huntingtons has RWS 280 brass. Its expensive, but many say its as good as Lapua. Just in case you go that route and really care about case quality. 60, or even 40 cases might be enough if this is a hunting rig that you don't shoot tons of rounds through.
For me, having to fire form the cases is not a biggie. I find cases fired in my gun and then resized to keep the shoulder in the same place end up being my best for accuracy.
