It is a major risk to sell them, But at the moment the party hat market is like a 5 year old on red cordial. Its up one mintue down the next, I spose if i was in you postion i would sell a mask set and how ever santas i needed to buy a blue party hat, hold onto it till next winter than sell it. My guess is that the price increase in a rarer rare is more than a common rare. But i advise you seek proffesional merchanting help,