Mademoiselle Tyler and La Belle Mademoiselle Sydney are wearing historical costumes inspired by Charles Worth from the mid 1800s. Both are limited editions of 100 pieces. In addition, there was a limited edition Phantom of the Opera and Christine Dae doll set. You can check out some more pictures on this link.
I've seen the single Tyler and Sydney dolls selling on Ebay for a BIN price of $499, and The Doll Peddlar has both in stock for $599. The Phantom of the Opera set is listed at $999.
Photos courtesy Tonner Doll Company.