If they are not limited editions they may still be in production. If they were limited editions they are probably completely sold out and will not be manufactured again.
Try eBay if you really want them. You can't buy HM mystery packs, LEs (unless they are really unpopular), or retired pins. Try looking for your pin on www.odpt.com and you can email WDW Mail order. Shipping is expensive directly from disney, however.