Simplest solution would be to just remap keys you don't use with something like Autohotkey. If you want a separate keypad a cheap solution would be to use any

Simplest solution would be to just remap keys you don't use with something like Autohotkey. If you want a separate keypad a cheap solution would be to use any old keyboard and then remap that one specifically with a tool like http://www.hidmacros.eu/whatisit.php http://www.hidmacros.eu/whatisit.php (optionally you can paint or add labels to the keys to make it easier to use).