The cluster probably has an internal fault or power problem somewhere. If youre handy with that kind of thing, try to remove it and test it with a multimeter, its probably dead.
Best advice is just check junkyards regularly and ebay for a cheap replacement from another wrecked 323.
<img src='http://members.cox.net/inelson5/330i.jpg' border='0' alt='user posted image' />
<img src='http://members.cox.net/inelson5/wooani.gif' border='0' alt='user posted image' /> The whistles go WOOOO!!! *BUBB RUBB FAN CLUB*