That's some very unfortunate news for you James. It's going to be a tough road to hoe to find a replacement. Yes, new wood could be made at a cost of several hundred dollars, however; the forend iron will be the tough part to source.
Here's an alternative suggestion: Assuming you know the general location of where you lost it, I would contact a local scuba diver to find it for you. A scenario similar to yours a local diver here in Wisconsin was recently hired to find a lost $4000 prop for an individual's sailboat which was found and retrieved by "Ed the Diver". Google him or here's a link to a facebook account of the incident:
https://www.facebook.com/reel/2661712720849065