I, too, bought from BassPro (Triple 7 powder) as it was the only place convenient and they charged about $33. But for months they didn't have any 3F which pushed me online. And that was a good thing for a few reasons as I had also been quite interested in trying real black powder but required a more energetic powder (Swiss), but NOBODY had it.
I found that an order of 3 lbs from Grafs of T7 with the HazMat fee about broke even to going to BassPro, but without the concern of wasting time and effort, but also that I could get real black powder, which by then Olde Eynsford had become available, which is much more cost efficient, an American product, and still just as energetic and for a mere $1 more than standard Goex, which by all accounts produces much less fouling in comparison to the standard stuff.