maybe you should just drive a few more miles across the Piscataqua Bridge to Portsmouth, New Hampshire
What'd I miss in Portsmouth? I pass through it to get to Kittery. Great town, but no BP that I know of. In fact, I don't know of any place in NH that has BP. Rileys used to but the state shut them down due to storage problems.
If you do decide to go to Kittery for powder, call first - they were out of it (and caps) last week.
Because Kittery was out of Goex, I've been using Pryodex FFG in my ROA with great results, even better than Goex FFFG for some reason.