I am sorry but i believe it would be a very bad idea.
1st that is labeling every item of that class a dupe, not just a duped one. secondly, who here is an expert on what exactly been duped or not? ive seen about 15 pairs of silverware in the last 2 weeks come up for sale, does that mean there all duped?? who here is a expert on whats duped. and the question to that "expert" is what proof he has that said item was duped? just because a lot of one item or another is suddenly out on the market doesnt nessesarily mean its duped. in my opinion there is only 2 types of people that can honestly claim whether a item was duped or not.. the ones who duped it to begin with and those members of uo staff with the ability to track duped items in the first place.
I have heard quite a few times that a certain unique rare or event item that is owned by a person with almost unquestioned integrity. and then new ones pop up. which could mean one of 3 possible answers.
1. the persons integrity is now questionable
2. someone found a way to dupe a item while its in someone elses possesion
3. the item is not unique.
lets face it no one on these boards knows for sure what has and has not been created on a asian shard. they work with there own set of rules and have events and activities like we do. i would not be suprised one day one of there em's spawning 100 of one server birth if it suits there event arc. there past can prove it. then lets not forget the allegations of questionable actions by certain gms and other higher ups in the asian side of uo. and there rumors.
so unless you work for era/mythic you could not possibly know if a item is duped, unless you were present when it happened or did it yourself. either way you wouldnt belong on these boards.
now mind you if i saw a asian event where you killed a event mongbat and looted one of those 1 bil+ event items i would laugh by butt off! and i wouldnt feel sorry for the owners.