..purple heart wood cut so the grain tends to run vertically to minimize risk of fracture. I'll leave the horns about 1/2" thick or so, the "crotch" will hold up to 1/2" or 5/8" line (It's a small boat) and the gap between the horns will be mebbe 3/4", mebbe 1" wide. The horns don't want to be too long or too short. Better, I reckon, to start with too long rather than to have to try to add into them if they were too short.

This would be on a 1" wide base and let into the toe rail at all four corners of the boat. It would either be flush or slightly proud depending on the need for the design. I'll have to sketch it out. It'll be basically an eyeball job as I have no numbers.