Found a Logitech G15 from Kierrätyskeskus for 3 euros, it had an US layout and defective key backlighting, but the LCD backlight was much, much brighter than my old G15.
As the LCD is the only reason I have been keeping my G15 and haven't gotten a better keyboard, I decided to try my luck. After a few hours of cutting and grinding, I now have a nice LCD that fits the hole on my monitor stand. The LCD is running LCDhost with my own layout, and would work even without the logitech gaming crapware.
There quite a few tradeoffs with this mod though:
The slider on the right doesn't do anything, as it toggles the windows key on a hardware level. Mute and brightness buttons on the right don't work either, as they were part of the keyboard matrix. I could trace the matrix and add switches, but as I never use the buttons, I can't be bothered. Cutting them off isn't an option, as the PCB is too wide and goes under them. There is no backlighting for the media buttons, both because the LED mounts were at the front of the keyboard and were cut off, and because the original LEDs were defective. Adding my own wouldn't be too hard as the volume scroller required me to keep the part of the diffuser layer under the buttons, but I didn't feel like soldering.
Here is another way to tackle this same thing, just using the LCD and bare PCB - http://home.comcast.net/~davemats/lcd_panel.html