An anemic and long-obsolete round. You're going to have a tough time, frankly.
You might find some in gun shows.I have one book saying you can rework .32-20 cases to make yours, PM if you want the info.
I hear Load-X Ammo in California makes it periodically, but how'd you get it up here legally I'm not certain, given the export control stupidity going on these days. Gad Custom Bullets also list it, but the same problem applies.
Good luck.