The primary radio you purchase for your vessel should be a marine VHF radio (FCC Part 80 type accepted)  There are many options available.  As an auxiliarist, you may be able to get GSA pricing on your radio.  This price will generally be around 60% of the list price.  Additionally, many dealers will also give auxiliarists a discount.  You should get a radio that interfaces with a GPS receiver.  Make sure you get an MMSI number and program it in.  This will allow other auxiliary vessels and the Coast Guard to quickly determine your position.  A combination radio and GPS with a decent sized display is even better.
 

As a second radio on your boat or a radio for your vehicle, I would recommend an Part 90 type accepted commercial radio.  This type of radio is now required for operation on our Auxiliary VHF radio frequencies and repeaters.  Using this type of radio through the repeater system that we are building in Oregon and Washington will give you wide radio coverage with other vessels. 
 

At this point we have the software to support the ICOM F-121 radio.  It has 128 Channels and can be programmed for Marine and Auxiliary VHF frequencies. If you ever get a Ham license it can be programmed for that as well. It is a very solidly constructed and meets Mil-STD-810 shock and vibrations specifications. You can get the specifications at:

http://www.icomamerica.com/products/landmobile/f121_series/default.asp

The GSA price is $251.00 from ICOM America at 800-872-4266.