Remapping the Arrow Keys/home/end/etc


I realize you can remap the letter keys.
I want to use a very compact keyboard that won't have any of the keys to the right of the Backspace/\/Enter/Shift/Ctrl buttons. I definitely need the arrow keys and perhaps the Home and End keys.

Anyway I want to hit a keyboard command which will convert:
i > up arrow
k > down arrow
j > left arrow
l > right arrow
and perhaps some others.
Then I need to revert of course.

Is this possible in OSX? Using an older G4.