I have two eyepieces for sale: Kasai 6mm and 9mm (9mm SOLD).
Kasai is the OEM for UO Orthos and are well know for their quality.
These eyepieces are in Mint condition.
No set screw mark. Optics is as clean as new.
Each comes with original box and a homemade eyecup. The eyecup can put your eye at the right position to see the entire FOV but avoid hitting the lens.
Ask for $40 each. Price include shipping to most part of the world (including CONUS).