Evelyn will offer the party a spell bottle , the price is non negotiable and if the party refuses there will be no second chance:
The cost is the color from one of the characters eyes
Evelyn is actually of the Fey and a powerful sorcerer
A great traveler, Evelyn wanders the length and breath of the The Thousand Isles but rarely misses the Festival or The Pirate Market.
Her pack mule is known to be filled with odd treasures which she refuses to auction or sell, offering them to random people she meets at the market as the whim takes her.