Indy Cylinder Head Show, Indianapolis, IN. March 7th and 8th

That's a pretty good list of vendors most guys would be looking for. The way the meets have been dwindling, that's probably the size of Carlisle. The only advantage would be more individual vendors at the PA meet. I don't think Indy has been there lately or Mancini.
I have a booth at Indy, been the last several years as well. Indy is probably closer to the Mopar Nats in terms of swap meet size. But it's no where NEAR Carlisle. I never got thru Carlisle despite spending an entire day there. The Nats and Indy booth can be gotten thru thoroughly in about 4 hours give or take.