Your photo shows a seat post known as a "hairpin" style seat post.
I will look to see if I have this style or the "L" pattern.
From the photo you posted it looks like a Kirkpatrick saddle found on Columbia and other make bicycles of the era.
What make, model and year bicycle is it going on as these posts varied in diameters between the seat and bicycle manufacturers.
Mike Cates
(760) 473-6201
cates0321@hotmail.com