Inherited two OLD .32 S&W Long revolvers

Question for anyone who may know.
I inherited a Forehand Arms break action revolver chambered in 32 S&W Long and a Harrington and Richardson Hammerless revolver chambered in .32 S&W.
Information I have researched indicates that I should not use modern ammunition and either of these revolvers and should only use black powder rounds.
Does anybody know of
1) a source for black powder ammunition commercially, or
2) a reloading recipe for these calibers.
I have a RCBS rockchucker reloading press fwiw.
Thanks and Merry Christmas!!

The Break top might fly open with heavy modern loads. I shoot 1.5grs to 1.9grs of 231 Win or Bullseye powder under a 98gr hollow base wad cutter for NRA bullseye competition. And they are both mild.
You could try a load of 1.5grs of 4fg(ffffg) black powder under the 98gr SWC or hollow base wad cutter to start. The hollow base wad cutter loaded inverted makes a great close range defensive load for home protection.