I used a Ritchie flush mount(http://www.ritchienavigation.com/explorer1.htm) which I bought from Hamilton Marine (http://www.hamiltonmarine.com/ get a catalog) and then flush mounted in a glassed in wooden ring in front of the cockpit (http://www.pete-and-lisa.com/kayak/images/compass_detail.jpg).

Highly visible and low profile - has worked very nicely.

Ritchie also now makes a Kayaker model that looks good.