You and Your Big Shrunken Head

S5 E5: When the Douglases Eb and potetentially wealthy Arnold return from Chicago the pig goes on a gift-giving spree. Mr. Kimball gets a wristwatch Lisa an expensive braclet and Oliver a shrunken head. With Arnold the target of every salesman in the valley he hides out at the Douglas farm. Soon they've tracked him down and it's Oliver who has to fight off the pushy peddlers.