In that case, check the 4-digit number. You may be able to find software that will work the keyboard that way.
My keyboard is a SK-2501 for example. It was labeled as a Lite-on keyboard, but I could not find software for it on Lite-on's website... that's when I did a search on the SK-2501. Found Silitek's site and discovered a lot of keyboards with volume and other controls were actually made by them. Compaq, NEC, and a few others used keybpoards originally manufactured by them. (I hooked up a Compaq keyboard to my computer which has Silitek's software installed and all the functions worked.)
<font color=red> If you design software that is fool-proof, only a fool will want to use it. </font color=red>