If you HAVE to have a Lilly, here's where I would check:
RE-Lilly Facebook group
Gently used and New Lilly
https://www.facebook.com/ReLilly.Gro...Resale?fref=ts
Zappos
New dresses (a little less expensive, but not much)
http://www.zappos.com/lilly-pulitzer-womens-clothing~7
If you REALLY want to hunt you can search Ebay and Shopgoodwill.com and if you find something that works, have it dry cleaned:
Lilly at Shopgoodwill.com
Completely random and of all vintages
http://www.shopgoodwill.com/search/S...&showthumbs=on
Lilly on ebay
Less random and more new stuff
http://www.ebay.com/sch/Dresses-/638...lilly+pulitzer