The issue with real black powder local is governmental regulation. Most shops don't/won't deal with that red tape to stock it and if they did, they'll charge accordingly. If you have to mail order, a pound or two is not economically viable. Best to order in bulk or with a couple others to amortize the hazmat across a large order.
Since I shoot competition, I go through lots of powder. Luckily, there is a black powder supplier right outside our organization's home range and I stock up twice a year. If anybody I know is heading that way to a match, guys in my area will put in an order for pickup if we're not going.
Good thing about dealing that way, we've had no issues in either powder or caps recently.