Actually to be even more specific, DON'T buy that Short Column!
What your legs will come with is a 70mm tension adjusted opening into which a flat plate is now installed.
Into that opening you install a 75mm bowl for video heads and other leveling devices, or a crank column or what is called a "Rapid Column"
Look at this picture;
Image hosted by forum (
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© CyberDyneSystems [SHARE LINK] THIS IS A LOW QUALITY PREVIEW. Please log in to see the good quality stuff. This is a rapid column assembly for a series 2 or 3 set of legs. You need the whole assembly. The columns is just the innermost part. That large diameter disk like thing in the middle of the image through which the column goes, is the part that will fit the 70mm opening of your tripod.
The "column" you want to buy is not the whole package. It won't fit into the 70mm hole of your tripod, as it's only about 25mm in diameter. What fits into the 70mm opening of your legs is any of a number of items including the collar that would hold a rapid column like the one you link to. That shorty column is for tripods that already have a collar.
HOWEVER, until you find a rapid column collar, you don't know yet what column diameter to get. You may end up with s series 3 collar, in which case that collar @ B&H might be too narrow to fit.
This also starts to explain some of the big price difference, Compare just a short center column with an entire assembly, and of course they won't be priced at all alike.