Our Nauticat has several (6) large aluminum chocks, which are morticed into the perimeter teak toe rail. They were originally made by a Finland mfgr and available through Meredian, a chain & mail order, marine supply store in Finland, their answer to our West Marine.
In searching through the online catalog though, I couldn't find the exact item and don't have a close-up photo of a chock. This Photo of my starboard boarding gate shows the chock between two boarding ladder clips.
The chock has square ends allowing a flush installation to the teak . . . nice, unobtrusive design.