Welcome to the Forum.
It is a Dive Knife and the Tip is bent to pry Coral or Abalone or hatches of Wrecks.
I think the one You lost was a Wenoka.
I do not think it is made anymore.
You might Google "Dive Knives" and see if there is anything Close.
I think it is no longer legal to gather Coral and Abalone is very closely regulated.
It Seems that the Dive Knives offered today are more geared to Sport Divers so they are much smaller.
Hope this Helps.