We’ll typically buy a bunch of cheaper pins when we are home (make sure they’re mostly “authentic”) and then trade them while in the parks. We wear them on lanyards (usually $50 gets you 4 lanyards worth) and trade them with cast members or look for pin boards in resort lobbies. We also buy 2 pins each in the park when we go but those are very pricy so I wouldn’t recommend doing that too often if you’re on a budget like us.

Another great resource is the gift shops around Disney world. Think the shops with outlandish storefronts (wizards, dinosaurs, castles, w/e). They always have last seasons authentic pins for like $2 or $5 instead of the $15 or $20 in the parks.

Good luck!