Any one heard of these and where to get them?

Anybody know what type of battery the Tekna Computek dive computer
takes.  I removed my battery when I put the computer into storage,
can't find the old battery, Tekna has been out of business for a
while, and I can't find a dive shop that has an old manual to look it

On the news they had the bloke who was  attacked the other day.  They
interviewed his dive buddy who put the survival down to a shark repellent
device strapped to his leg.  Has anyone ever used these?  How do they work?
Pat