I doubt you'll ever be able to walk into a store anywhere and find it, order it online from a semi custom ammo maker, maybe. But the biggest issue is for them to run well in the 28 and get the performance to justify using them in the first place, you have to have a lot of freebore and seat them to 3.700"+ which is almost .4" over SAAMI spec. That's massive difference.
They hampered the round hard going by SAAMI long action specs. Loaded at 3.340" You aren't getting much over a 7 mag. But if you hand load and get a barrel chambered with some free bore, you can really make it shine. I'm shooting 195's at 3.720" COAL with retumbo at 3040. Lots of people are using RL33 and getting 3150, I just chose Retumbo for it's temperature insensitivity.