I got a couple boxes last week from HSM in Stevensville, MT.
They have a website and they will ship anywhere. Good place for components and loaded ammo.
I was in the store with a list, and they filled the order including 2boxes of 300gr Bergers. They have a large inventory of Berger bullets and other stuff you can't believe. They are not well equipped for retail but they try. HSM is an ammo manufacturing company with contracts all over the world so retail sales are just a side line to them. I grew up in that area and have known the owners for decades.
Just good old boys who haven't changed much except they drive nicer pickups and take neat vacations now. Phone: (406)777-2106 and explain to Rachel at ext 102 that you really want to find some of those bullets. Wouldn't hurt if you had a few other things to order too. Their prices have always been very good and the stuff they have in bulk is super good pricing. Good luck.