I don't think an item like this exists, but I could be wrong. The only -50hp cesta requires blood magic.
(https://wiki.guildwars.com/wiki/Grim_Cesta) says they are only currnetly available with either curses or death magic requirement, though the knife one from the quest requires blood magic, and is used for the 55 monk.
If I'm not mistaken the cesta used to require healing magic instead of blood magic at first (for a short time) and this would therefore be a pre-nerf item. Also recall someone else selling one like 2-3 years ago orso back when Guru was still up, and it fetched quite a hefty price then (considering the market at that time). Someone correct me on this please if I'm wrong.
As for PC, impossible to say. Put it up for sale and see where it goes.
EDIT: Found an old PC thread in the archives from guru with picture:
http://archive.guildwarslegacy.com/08/08%20Price%…bossed.001.html
EDIT 2: To clarify what I meant with the cesta used to require healing magic I meant specifically the -50hp quest reward, not Grim Cestas in general 
Agreed with Coffeeman, and I have added it to my truth about pre-nerf thread.
Yup, had one a few years ago. If archives have it, I had a thread on Guru about it
