mk-80 (blue switches, NKRO via PS2), mk-85 (red switches, NKRO via usb), Sidewinder X4 (not mechanical, NKRO via USB), K90 (red switches, NKRO via USB, not fully mechanical), a lot of keyboards have 20KRO, plenty unless you faceroll. Probably a few by SteelSeries, CoolerMaster... Plenty around. Look for their features.