A bowling balls diameter ranges from 8.496727273" to 8.591545455". While 10" schedule 160 pipe has a wall thickness of 1.125" leaving a bore of 8.5".
A bit of a tight fit. If you use schedule 60 seamless X-60 pipe you would have a better fit and lower pressures.
My .223 cents worth.
I know where to get the pyrodex and fuse.. I actually have a bit on
hand at the moment, but it's old. (Don't ask.)
Collectors Firearms on Richmond carried both items last time I checked.
Waterproof fuse, great stuff, burns under water.