First, you ought to know that from now on, holiday drops are no longer tradable. We don’t know why Jagex did this. Maybe the holiday drops and rare items show how long that somebody has been playing, so you can show them off as an achievement.
Now it’s time to get down to the specifics of a few of the more popular holiday drops. Pretty bad graphics by it’s one of the rare items in runescape account, presumably its value will constantly increase.
Santa hat is very rare and highly priced. Not sure about how much it costs compared with the party hats. The last tradable rare runescape item is the Halloween masks, which could have been picked up on Halloween 2002. There were only 3 colors and other than that, they looked exactly the same. You can buy runescape accounts with awesome items.
If you need them you must either shell out huge sums of money for the elderly ones that are tradable, or wait until the next holiday event to be able to get your own.