There is only a single location where players are able to purchase Pears in Bulk which is in Iron Marches. Peaches are sold by Braxa Scalehunter. Now before I get started with telling you the two locations keep in mind in order to purchase any goods from a Karma vendor you must first complete the quest they have for you. That is of course if they have a quest available if not you'll be able to buy whatever they're selling right away.
The Braxa Scalehunter is located in the southwestern end of Iron Marches to the north of Champion's Shield and south of Monger's Sink. You can take either the Old Piken Ruins Waypoint or Village of Scalecatch Waypoint to reach him.