Help me buy a new headtracker

Hi everyone! I'm a quadriplegic (paralysis affecting all four limbs) who needs a head tracker, a device that allows hands free use of a computer, to get my work done and use a computer.  My current head tracker is about ten years old and no longer accurate.   I am currently also replacing my power chair and need help purchasing the head tracker.

I'll continue to work toward earning money to buy this, but any amount, no matter how small, will help. I appreciate your generosity,  whether you're able to donate or just spread the word.