Plucked Turkey is first seen during the Halloween quest two years ago. They were about 10m back then. However, the same quest is offered to players again last Halloween, so their value somewhat decreased. I guess they're about 2.5 - 5m now. Harvester's blade is about the same (since you get it by giving a plucked turkey to a butcher, but the turkey disappears), if not more.
Its price might increase if the same quest is not offered this Halloween since Harvester's Balde is quite a useful item.