That lists a lot of things but not all of them. Here is what i know off the top of my head 60k armor horses stable vouchers vault vouchers treasure vouchers IcC birthday voucher haunted head valentines day rose egg nog haunted head haunted candy labor bench turkey slicer independence day firework empire firework mob arena swords and bows instructions rudolph the new pick supporter voucher
2012 Empire New Years Firework 60k Member Items Independence day and 2013 Empire Firework Promo Horses Haunted Head Turkey Slicer Holiday Pick and Rudolph I didn't include special items, just items that were actual promos. I would have to say that the 2012 Firework or an Ore Buster are in the highest demand right now.
There are two empire fireworks with the 2012 one being really valuable. There are also two valentines roses. As with the fireworks, the older one is more valuable.