Cross border shopping has taken a terrible turn, you have to be very watchful of what you can and CANNOT have in your possession in case you are stopped by US homeland Security.( And you will get stopped, with hefty fines )
The list of forbidden products are vague and hard to find, so do your homework, before you cross the border, or you WILL PAY!
I have been a black powder shooter for over fifty years, things have gone downhill at a terrible pace.
Higgonson Powders in Hawksbury, On. are a good supplier, but you have to drive there to get powder & caps.
Lead is becoming a hazardous material, so you have to search well in your area to find some,
Look, it is out there. Plumbing stores, roofers, Bell Canada linesmen. Lead pipe from long ago is very good casting, do not use connections, or joints they are mixed with other metals.
Your municipal works often dig up lead pipe and is available IF you ask nicely.
Wheel wights are good only for smooth bore guns, it is hard and won't compress. Also lead is no longer used to make wheel weights, so even that is becoming unusable.
Browning solution is hard to find or buy as it has a nitric acid base, making it a hazardous material, and the permits required are not worth the small profit margin to bring it in.
If needed, I can send you a list of materials to make over two gallons of browning solution. That should keep you going for a month or two. ( Yeah, I know TWO (2 ) GALLONS )
Have a great day!
Fred