The cleaning is not only NOT easier, but more involved. Triple 7 requires both soap and water, and then modern gun solvents to remove the residue in the barrel, flash channel and nipple. It costs more twice as much as Black Powder, degrades from being exposed to oxygen, so that it begins to lose its power within a few months, where black powder remains the same for centuries if properly stored.
If you can't buy black powder locally, Then plan ahead, contact Graf & Sons, or Powder Inc. to find out their minimum shipping order policies, and then order powder. It is delivered to your door within a couple of days. No, you can't order it the night before opening day of Deer season, and expect to have it on time. But, with only a little forethought- I know that is a big word to some shooters- you can have your powder in plenty of time for this year's seasons.
Powder orders should have been made last June, so you had all summer to shoot, work up loads, get used to the gun, and fix anything about the gun that is not working right, rather than wait until late September to decide you are going to take the smokepole out and hunt with it, if you can find some powder! If you can't get to a range and check on the load, loading procedures, and cleaning procedures, use something else this season, and plan to use your gun next year instead.