The eastern Indiana/western Ohio border is kind of long. Are you more south or more north?
If more north, I can't help a lot, but there is one club, Pequannah that is pretty much centrally located for both north and south. It’s located around ten miles north of Winchester, IN.
Southwest Ohio has several clubs, The Cincinnati Muzzle Loading Rifle club, Dayton Muzzle Loading Gun Club, Fort Greene Ville Muzzle Loaders, and Simon Kenton Long Rifles. I’m sure there are others, but these are the ones I know of.
My local club, Wahpanipe, located a few miles south of Glenwood, Indiana, is strictly chunk gun now.
Closer to Indianapolis are Blue River Longrifles, Conner Longrifles, Wetzel Trace Longrifles, and Morgan County Longrifles. Near Batesville, Indiana is the Tri County Coon Hunters.
As you can see, there are plenty of clubs to choose from, and the schedules are usually staggered enough that, if you are willing to do a small amount of traveling, you can shoot somewhere just about every weekend.