I know of about 500k fishermen that would love to see this trade take off. They are really big really aggressive and very destructive. Ruin hundreds of thousands of dollars in netting and fish loss. The only natural enemy I can think of is the killer whale. Not so common in the harbors where the sea lion have begun to remain (due to the abundant people food).

I bet you could make quite a few from their massive hide.

The problem as I see it is the crappy cantle supply. I've got my wife working on that now. Quality at a reasonable price. Notice the emphasis on quality. Those stamped tin cantles are terrible.

I'll get back to you all when I see a bit of interest and I can get this moving. Seriously.