Without knowing what bullet shape or weight you ordered, nobody can address the charge question.
Hodgdon's load data includes HP-38 data for a 115 grain lead round nose (LRN) and for a 125 grain lead conical nose (LCN) bullet.
Alliant only has 9 mm data for Speer Gold Dot bullets, but knock those loads down 10% for same-weight lead, and you are likely to do OK. You can then work up slowly, watching for
pressure signs.
As to supplies, there is a shortage currently because the threat of new gun laws has produced panic buying and it coincides with the military and government agencies making stockpile orders for ammunition. Lots of competition. The supply lines are supposed to start catching up some items next month.