When you say circumnaurul headphones and visible mic boom there really aren't to many. I think I have only see a few as most of the headsets I have seen which use that headphone style they have the omni directional mic.
If you are looking for a good solid wireless mic then some like this;
http://www.newegg.com/Product/Product.aspx?Item=N82E16826106040R Plantronics is a little on the expensive side however their mic quality it top notch. These are actually the exact models we use here in the office and can personally say the range is very good.
Here is another option as well that I found which you can use your own headset if you like.
http://www.newegg.com/Product/Product.aspx?Item=N82E16836117701 Edited, Nov 1st 2007 11:42pm by xXBijiontXx