There are only two that work with a modern computer, the 900886 (Ps2) and 900840 (DIN). All the WYSE PCE keyboards have a "normal" layout, so you'd be getting a pretty full complement of switches. My WYSE PCE (terminal version of the above) is number 840358.
Other than that, you can get them pretty easily on ebay, but they have less switches, and not all the keycaps will work. I have a keyboard from a WY-30, with a sweet layout (like a poker with a tenkey and a 9.95x spacebar) model number 840013. A better bet is to get a WY50 or WY60 one. The Wy50's should have thicker keycaps, but the ones on mine were stepped. The WY-50 keyboard is 840059.
If you want, It would probably be possible for me to to mail forward you one from ebay. I could take the casing and keycaps off, and it'd be under 4 lbs (First class mail international) for sure.
I have four, (one in just a set of keycaps), and I think I paid less than $20 shipped for each.
Only get beige ones, and don't get any with a windows key.
Here's two of them for $25. I want another WYSE, so I'd happily split you.
http://www.ebay.com/itm/2-EACH-WYSE-PCE-KEYBOARD-840358-01-/160879264229?pt=PCA_Mice_Trackballs&hash=item257526c1e5
