Those are two very different things. Belaying pins: they can be found (usually 1/2") in bronze or galvanized online by googling. Mine are hardwood, turned (by me) on a mini lathe. My pinrail is doug fir, bolted through the side of the cabin
(I see no earthly use for a pinrail on the shrouds--not usually strong enough to make halyards fast to, and in an awkward position to use if you're hoisting the sail anyway).
I wouldn't consider ratlines unless I absolutely had to make a habit of going aloft when the sail was down (when it's up, you can just climb the mast
hoops). If you have that old-fashioned stainless steel
, then the friction tape and seizing in every place you attach a ratline traps moisture and leads to crevice corrosion
. If you have proper dacron-covered plastic shrouds, you can just use 1/4" line firmly constrictor-knotted around the shroud
. If you need thicker line for the rats, lash it onto the shroud
with heading twine.