The Rodin Museum is a little replica of the one in France. I’ve been in both and the French one is obviously much better, but if you hadn’t been there, I strongly recommend you to visit the one in Philly.
They have a replica of “The Thinker” statue and of the “Hell’s Gates” (one of my all-time favorite sculptures). These replicas are open to visit freely.
If you want to enter the museum, I’ll cost you a “suggested contribution” of 5$. Mondays is closed.