Hey Jess,
If you are anywhere near Milwaukie, Oregon, I've got a crapload of Winchester factory ammo for the .243WSSM.
And I have even more .223WSSM Winchester factory ammo.
Nope, I won't ship it ... way too complicated. But, if by chance, you live in my area we can work out a great deal for both of us.
God Bless,
Steve