I saw those. They look like 1390120 variants with no LEDs.
What are the chances that they are terminal boards?
As far as I know, you can tell which are terminal boards because they have the extra key on the tenkey (+ is split into two). I'm not aware of any PC-compatible keyboards that did that.
so: pretty good chance they are not PC compatible.
BUT it should still be largely the same thing, right? If you take a Soarer flashed arduino and pull out the ribbon cable connector and hook up to teensy instead, Soarer will do his magic and keyboard will also be magically plug and play for USB too? And if you run just 3 more cables for the LEDs, you will also get LED support?
For that kind of price I am willing to throw in some cash to find out. Dorkvader, interested? I want a keyboard with one permanently on LED though. Would like to have my slow blink LED
always flashing so that keyboard looks as though it is breathing whenever it is connected.