The importer has around 6,000 lb of Varget on order from Hodgdon powder and actually received just over 1,000 in the shipment of a few weeks ago which is now mostly with those retailers lucky enough to be allocated any. That 80% shortfall makes it pretty plain that there will be a lot of disappointed retailers and customers.
The same applies to H4350 and H4831sc although not quite as disastrously. The others mentioned (H380, H414) aren't in short supply as they're manufactured in the USA (General Dynamics' St. Marks Powder Co. in Florida) - the shortages are in the Australian (Thales / ADI) manufactured grades due to shipping health and safety regulations betweenh Sidney and the USA which have reduced explosives consignments to a single container per shipping move compared to two which used to be allowed.
There are alternatives to Varget, the main one being Reload Swiss RS52 which does an identical job using similar charge weights and gives superb results. RS62 is an excellent substitute for H4350. IMR-4895 and 4350 are plentiful and are unaffected by the shipping problems being manufactured in Canada at another General Dynamics plant. The first supplies of the new IMR Enduron powders have arrived here - IMR-4166 which has a burning rate and loads data close to IMR-8208 XBR and H4895 with the same applications such as .308 Win. The slower burning (similar to 4350) IMR-4451 should arrive in a future shipment. Data are available on Hodgdon's online ineractive Reloading Centre website
http://www.hodgdonreloading.com/
and show 4166 velocities similar to those for VarGet in some combinations, (eg 308 Win with the 150gn Nosler BT) but usually a bit down. American shooters' responses to IMR-4166 have been on the whole very positive.