It is hard to beat a Timex from Campmor http://www.campmor.com/- you can generally get an Ironman for under $20 and a basic dive style watch for under $30. I have had both my Ironman and dive watch down to 170'ish. I personally find the dive style preferable since it is easier to read in poor vis - hit it with your dive light and it will glow for a couple of minutes. No need to push a button for the backlight (although it has one).
Just checked their site and they have a decent dive watch http://www.campmor.com/webapp/wcs/stores/servlet/ProductDisplay?productId=39201808&memberId=12500226 for $19.97 and a little different model http://www.campmor.com/webapp/wcs/stores/servlet/ProductDisplay?productId=39193484&memberId=12500226 for $21.97. It is hard to beat those prices.
Jackie
Just checked their site and they have a decent dive watch http://www.campmor.com/webapp/wcs/stores/servlet/ProductDisplay?productId=39201808&memberId=12500226 for $19.97 and a little different model http://www.campmor.com/webapp/wcs/stores/servlet/ProductDisplay?productId=39193484&memberId=12500226 for $21.97. It is hard to beat those prices.
Jackie