Legal environment of business discussion question

Imagine that you are at a flea market and you are looking through a table full of old books or every type. You discover what you believe to be a first edition of Mark Twains’ Huckleberry Finn, although you are not certain. The price on the book is $5.00 and you gladly pay it without question. Neither you nor the seller discuss the book in any way as you purchased the book. Afterwards, you have the book appraised by an expert antique book export, who informs you that the book is worth at least $10,000.00. 

In this exchange, you have provided $5.00 in consideration for an item worth circa $10,000.00 when sold in the correct market. Could the flea market bookseller properly seek to have the sale set aside due to inadequate consideration? What is the flea market bookseller knew it was an original, but had no idea of the true worth and thought that $5.00 was a reasonable price? Will the law consider the issue of adequacy of consideration in this instance?