They are also pretty easy to just make yourself...
I have two sets, one for a .404 Jeffry sized body that also works pretty well with the typical .375 H&H cases, and one for the .30/06 size (.470), which works OK even down to .440 diameter cases, like the .22, Russian & 6.5x54 M-S. I suppose it would be best to have one for each body diameter, but I don't think it's really needed.
FWIW
I *could* make a 6mm on the .404 with these, but haven't (& won't). Did make a 6.5/404 "real short." Same capacity as the 6.5/284. Not worth the work.
Here's another heresy, based on sad experience: Resize dies for anything bigger than a .30/06 should be 1-1/4 dies, not 7/8 dies.