EPIRB

Hello, I have a Alden Electronics Satfind model S1015 EPIRB. The battery was replace several years ago, and according to the sticker was suppose to last until 5/09. The "test" switch fails to activate the light, so I assume the battery is too weak to operate properly. I have not been able to find any information about Alden on the web, except they are out of the EPIRB business. When the battery was last replaced, they also were able to perform a frequency test. I am fairly mechanical and could probably get the unit apart to replace the batteries. Performing the test is beyond my current capabilities. Does anyone know of a facility or repair shop that can "economically" replace the batteries and test the unit? TIA John