A photography store in Washington State put up two Meade 5000 UWA 1.25 inch eyepieces for sale on eBay, that have apparently been sitting on their shelves for a long time. One was the old 6.7mm (which I quickly bought), and an 18mm (yes, 1.25 inch format). I have one of the 18mm and it is a nice eyepiece. Its true field of view is as wide as you can get at 82 degrees in the eyepiece in the 1.25 inch format. I believe these were both made before they started waterproofing eyepieces and purging them with inert gas.
The 18mm is listed at $145 with $6 for shipping.
Just thought I would pass on the information in case anyone is interested. Just search on eBay for "Meade 5000 18mm" and it should show up, if it has not already been purchased.
I have been told that this 18mm eyepiece went away when they started waterproofing this series and was replaced with the 20mm in the 2 inch format. I suspect there was not enough room in the 18mm to get the seals to fit inside.