Better still try one of these.
Pains Wessex Fastfind Plus 406 PLB EPIRB
and complete the package with this
Revere Supply - HRU for EPIRBs
my company bought me the GPS Epirb and I am ordering the canister so I can take it diving. During any off shore work I do the EPIRB is on my belt.
Take your epirb diving, the ultimate dive accessory.