Try Bacon Sails & Marine Supplies - Discount Sailing & Boating Supplies
- a local shop here in Annapolis area. They have scads of used sails for sale.
Visiting them for a shopping day is a good thing to do as they have all kinds of used stuff for sail.
On the Chesapeake most days you will want a 130 or so, but if you can only get one in your budget go with a 90 or 100%.
Unfortunately the price of hank on as opposed to furling is you must carry a suite of sails to meet the conditions you'll meet on the water.