If you log onto the Goex website, they have a map of the country with names, phone numbers, and some email addresses for all their distributors. Call the one nearest you and see what they will do to sell you powder and get it to you. YOu can ask them if there is a retailer near you that still carries Black Powder, as they will know. Homeland Security regulations required expensive storage requirements to keep and store black powder, treating it as an explosive, and that is why so many retailers have had to stop carrying it. The law also requires the storage location be a certain distance from occupies homes. Since most gunshop want to be on a well traveled street for visibility, they are located in " strip Malls", with only a fence behind the buildings separating them from residential areas. The law requires more distance, so most of the stores can't meet the standard even if they will go to the expensive of having a safe to put the powder in.
Under the Member Resources, at the top of the index to this forum, you will find " Links". That takes you to a list of suppliers. Graf&Sons, and Powder, Inc., And the Powder House(?) in Maine come to mind as three sources that will sell powder in quantities as low as 5 lb lots, and still discount the price. The Government imposes a Hazardous Materials Fee on all shipments, of $20.00, so it saves you money to buy in quantity, even if you have to find some other BP shooters to join in with you in ordering powder. Cases contain 25 lbs, and you can mix the granule sizes in the order. ( ex. order 10 cans of 2Fg, 14 cans 3Fg, and 1 can 4Fg( priming powder) You can have two cases shipped to you in most states legally. The supplier will know if he can ship more than one case at a time to you in your state. By ordering in high volume, you can reduce your costs to about $12.00 per pound, a substantial savings over buying retail,and spread that Haz Mat fee over all those cans of powder.
The powder will cost a lot less than you pay for substitute powders! The Subs begin to go stale after you open the can, and have a fairly short shelf life after they are opened to air. Black Powder lasts forever, as long as its stored in a cool, dry location. Even when it gets wet, it can be dried and used. If subs get wet, they are done.