I'm not sure what's available in PA, but some other options are Rhum J.M. Blanc, La Favorite, or Neisson.

I am in OH, we have pretty poor distribution to state stores as well, but at least I can ship to my house from out of state.

Other commenters are talking about Haitian clairins, which - while not traditional for ti' punch - are similar in profile to rhum agricole, and also make a fantastic ti' punch. As does Rhum Barbancourt Haitian Proof (55% Haitian blanc), which again is different, but similar.

We can get some varieties of Barbancourt in PA, believe it or not. I've made my husband a ti punch with one of the higher proof Barbancourts. It was quite tasty. Appreciate the other suggestions though - will have to keep an eye out for them. Thanks!