Since no one is answering this inquiry for you, you cannot find a 3os primal helm with a T1 staff mod, because T1 staff mods can only roll on items that are <= ilvl24, and 3os can only roll on => ilvl26 primal helms. You *can* find 3os primals with T2 staffmods from a4 Diablo through a5 and normal cows, since they are all mlvl26+, but T2 staffmods cannot drop on => ilvl37 items.
Spear mastery, throw mastery, and oak sage are all T2 staffmods that are possible though, but very rare and require farming normal cows usually for sufficient density. Took me 3 seasons to acquire a +3 throw mastery 3os arreat style primal for my throw barb’s metamorphosis.
TLDR, you cannot roll a barb primal helm that is both 3os and has T1 staff mods (axe mastery).
Check the Amazon Basin topic for Primal Helms for more info.
Today I learned.