This is a Huygenian 12.5mm eyepiece that I got with some other stuff here on Astromart. I suspect it is the same as what you can get from Surplus Shed for $5.95 plus shipping. This is in good shape - I only looked through it once, and I don't even see any set screw marks. I will sell this one for $6.00, but include the shipping, as long as you are OK with USPS. If you want this insured and sent FedEx, we may need to re-negotiate the price of this valuable item. Sorry, but there are no endcaps or a box.
If you have some item for trade, let me know what it is. Maybe a piece of solar viewing mylar, or something else that would ship easily.